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  • Astronomy  (231)
  • Cell & Developmental Biology
  • Electronics and Electrical Engineering
  • Fisheries
  • 2005-2009  (387)
  • 1950-1954
  • 2005  (387)
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Keywords
Publisher
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  • 2005-2009  (387)
  • 1950-1954
Year
  • 1
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    Fisheries Science Collaborations: The Critical Role of the Community (2005)
    Details
    Publication Date: 2021-05-19
    Description: The present paper is based on a collation of information, through both a literature review and an internet search, on North American programs that involve some kind of scientific collaboration between fishers and fisheries scientists. It identifies four basic models of such collaboration and offers examples of collaborative activities that seem to fit into each of them. The first model defers to the expertise of the scientist for all major decisions and creates a strong programmatic distinction between what is science, and shall be done by scientists, and what are other, related activities that can be carried out by others. Various kinds of tagging programs, fisher advisory boards, at-sea research collaboration and many other activities fit this model. The second model, traditional ecological knowledge, recognizes that fishers have available to them a unique, local knowledge of the resource that can make a supplementary contribution to fisheries science. Several government, community and environmental groups are engaged in finding, recording and using this knowledge....
    Description: Unpublished
    Keywords: Mariculture ; Fisheries
    Repository Name: AquaDocs
    Type: Conference Material , Non-Refereed , Paper
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  • 2
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    Report of the meeting: Third Meeting of the Preparatory Committee For the Preparation of the Partnership Conference: Mauritius, 01 November 1999 (2005)
    ACOPS
    Details
    Publication Date: 2021-01-30
    Description: Dr Sebek introduced the ACOPS report which sums up the activities undertaken since the last Preparatory Committee meeting all of which are detailed in Annex V. In particular, Dr Sebek said that several strategic partnerships were being forged in order that certain components of the work programme, as agreed at the First Preparatory Committee Meeting in Nairobi in February, could start as soon as possible. A good example of such a policy, in the field of root cause analyses was the anticipated co-operation with UNESCO.
    Description: Published
    Keywords: Fisheries
    Repository Name: AquaDocs
    Type: Report , Non-Refereed
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  • 3
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    Interaction of Marine Turtles with Fisheries in the Mediterranean (2005)
    UNEP; Regional Activity Centre for Specially Protected Areas (RAC/SPA)
    Details
    Publication Date: 2021-05-19
    Description: At present, the impact of accidental catch on sea turtle populations is one of the most urgent problems that must be solved to ensure the survival of all these species worldwide. In the Mediterranean, too, all marine turtle species are affected by fishing activities, in particular the loggerhead (Caretta caretta) and the green (Chelonia mydas) turtles, which are more common than the others and are the only ones breeding in this sea. Since the Mediterranean populations of both species seem to be genetically isolated from the Atlantic ones (Bowen et al., 1992; Bowen et al., 1993; Laurent et al., 1993), fishing-induced mortality probably cannot be counterbalanced by immigration. This implies that the survival of the Mediterranean populations of these species depends to a great extent on the conservation effort that the Mediterranean countries carry on in the near future to reduce accidental mortality.
    Description: Unpublished
    Keywords: Marine turtles ; Fisheries
    Repository Name: AquaDocs
    Type: Working Paper , Non-Refereed
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  • 4
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    Emptying the Ocean: The threatened fisheries of West Africa (2005)
    Details
    Publication Date: 2021-05-19
    Description: The coastal waters of West Africa are among the world's richest fishing grounds ... for the time being. Droughts have ravaged the hinterland and as a result people have steadily moved towards the shores of Senegal and Mauritania. At the same time the international fishing industry seems intent on exploiting West African waters to a greater and greater extent. Nicolien Zuijdgeest and photographer Bas Beentjes visited the region and found that the sustainability of fisheries is being seriously threatened.
    Description: Published
    Keywords: Fisheries
    Repository Name: AquaDocs
    Type: Journal Contribution , Non-Refereed , Article
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  • 5
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    Gestion des Peches, de la Biodiversite et de L’environnement au Gabon (2005)
    Fishbase
    Details
    Publication Date: 2021-05-19
    Description: Le Gabon est situé en Afrique centrale avec une façade atlantique . Il est limité au Nord par le Cameroun, au Nord-ouest par la Guinée Equatoriale, à l’Est et au Sud par le Congo. La zone économique exclusive (ZEE) a une surface de 213.000 Km². elle est plus vaste que celle de Sao-Tomé et Principé, pays insulaire voisin (160.000 Km²). La façade maritime à une longueur de 750 Km , de Coccobeach à Ndindi. La largeur moyenne du plateau continental est de 60 Km, soit une surface à peu-près de 40.600 Km² de la côte à l’isobathe de 200 mètres. Ce plateau se termine par un talus peu abrupt, d’une longueur de 750 Km et d’une superficie de 11.200 Km² entre 200 et 800 mètres de profondeur....
    Description: Unpublished
    Keywords: Biodiversity ; Environments ; Fisheries
    Repository Name: AquaDocs
    Type: Working Paper , Non-Refereed
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  • 6
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    Biodiversity, Trade, And The Fishing Sector Case Study: West Africa (2005)
    Details
    Publication Date: 2021-05-19
    Description: In 1997, IUCN-The World Conservation Union, with the financial support of the German Federal Ministry for Economic Co-operation and Development, initiated a project to examine the relationship between the Convention on Biological Diversity (CBD) and the rules of international trade–those administered by the World Trade Organisation (WTO), in particular. The project was motivated by a widely shared concern that the aims of the CBD, which are essentially to conserve and equitably distribute the benefits of the environment, might be undermined by the WTO, which aims at the liberalisation of trade. Liberalised trade has the potential to integrate economies, regionally and globally, in mutually beneficial ways. But some observers are concerned that it may do so at a cost of impairing the environment and amplifying disparities in wealth, much of which, in poorer nations, is disproportionately represented in endowments of natural resources. Other commentators have claimed to locate synergistic potential, suggesting, for example, that trade law’s anti-subsidy disciplines might be conscripted into the campaign against environmental abuses such as overfishing.
    Keywords: Biodiversity ; International trade ; Fisheries
    Repository Name: AquaDocs
    Type: Conference Material , Non-Refereed , Paper
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  • 7
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    Marine biological research in Mozambique: past, present and future (2005)
    Royal Academy of Sciences
    Details
    Publication Date: 2021-05-19
    Description: This synopsis describes the development of marine biological research, including fisheries, in Mozambique. With around 3000 km of coastline, the living resources of the sea playa major role in the Mozambican society, mainly as a source of protein and income for the population, and of foreign revenue through exports. In the first years, after independence, in 1975, research activities in marine sciences were limited and mainly concentrated to fisheries through cooperation with Norway and the Soviet Union. A new era for biology started in 1985 when the Faculty of Biology at Universidade Eduardo Mondlane was re-opened. A 5yr curriculum towards a licentiate degree was introduced with a strong marine profile. Since the 1990s, a very dynamic de-velopment in Mozambican marine biological research has occurred. Several academic degrees in marine biology from universities abroad were obtained, and local expertise developed; building vital institutions and enrolling in advanced research activities.
    Description: Published
    Keywords: Marine biology ; Fisheries
    Repository Name: AquaDocs
    Type: Journal Contribution , Refereed , Article
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  • 8
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    The Fisheries of Eritrea (2005)
    FAO
    Details
    Publication Date: 2021-01-30
    Description: Published
    Description: Eritrea
    Keywords: Fisheries
    Repository Name: AquaDocs
    Type: Report , Non-Refereed
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  • 9
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    Rapport de la septième rencontre de travail IMROP/IEO pour l’étude des pêcheries de crustacés. (2005)
    IMROP/IEO
    Details
    Publication Date: 2021-05-19
    Description: Cette rencontre entre dans le cadre du programme conjoint de recherche sur les crustacés entre l’IMROP et l’IEO (Espagne)
    Description: Published
    Keywords: Captures ; Effort de pêche ; Length distribution ; Fishing effort ; CPUE ; Débarquement ; Landing ; Pêcheries ; Mauritanie ; Fisheries ; Accords de pêche ; UE ; Mauritania ; Crevettes ; Shrimps ; EU ; Distribution de taille ; Fishing fleet ; Fishing agreements ; Flottille de pêche ; Catches ; Crustacean fisheries
    Repository Name: AquaDocs
    Type: Report , Non-Refereed
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  • 10
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    Fish for Thought: Fisheries, International Trade and Sustainable Development (2005)
    International Centre for Trade and Sustainable Development (ICTSD) and IUCN-The World Conservation Union
    Details
    Publication Date: 2021-05-19
    Description: The Fisheries, International Trade, and Sustainable Development programme aims to inject both the sustainable development and natural resource management perspectives into the debate on trade and fisheries. The ultimate objective of the programme is to make international trade in fisheries supportive of sustainable development. The programme's main activity will be to convene a series of policy dialogues on fisheries, international trade, and sustainable development which will link processes and actors, and bring together all the different stakeholders' perspectives. Initially the programme aims to facilitate a process in which each stakeholder can move beyond the constraints inherent in his or her position, to enable all participants to step back from particular debates and stand-offs regarding fisheries, trade, and sustainable development-related issues such as subsidies, ecolabelling, or conservation measures. The dialogues, research, and information exchange process will seek to build common understanding and a baseline of shared information, and pave the way for participating stakeholders to seek solutions compatible with the aims of sustainable development by exploring ways to improve resource management while safeguarding the livelihoods of those who depend on fisheries, and ensuring economic growth for developing countries.
    Description: International Centre for Trade and Sustainable Development, IUCN — The World Conservation Union Publications Service Unit
    Description: Published
    Keywords: Sustainable development ; Fisheries ; International trade
    Repository Name: AquaDocs
    Type: Book Section , Non-Refereed
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  • 11
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    Focus on the Marine fisheries Research Division (2005)
    Accra : Marine Fisheries Research Division
    Details
    Publication Date: 2021-05-19
    Description: Ministry of Food and Agriculture
    Description: Directorate of Fisheries
    Description: Published
    Description: Exploitation, Upwelling, Pelagic species, Demersal species, Atlantic Ocean
    Keywords: Fishery policy ; Marine environment ; Fisheries ; Exploitation
    Repository Name: AquaDocs
    Type: Report , Non-Refereed
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  • 12
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    African Fisheries: Major Trends and Diagnostic of the 20th Century. (2005)
    IIFET
    Details
    Publication Date: 2021-05-19
    Description: The marine fisheries production from African coastal countries, combined with that of freshwater production of the continent is estimated to be 6 millions metric tons, corresponding only 5 % of the total world production. Africa's contribution to fisheries products (1,5 %) is insignificant compared to that of world commerce which is around 44 millions tons. This deplorable situation is due to a certain number of problems which include s among others, the relative biogenic poverty of African waters, the exploitation of African waters by foreign vessels, the total lack of catches effected by the African vessels out of their regional boundaries, the lack of knowledge on the mastering of commercialisation and on veritable commercial politics of fisheries products, including quality assurance. In addition to this, the almost inexistence of the aquaculture in the sub-Saharan countries. This paper analyses the African fisheries in the whole continent and presents the general characters, notably its evolution, fisheries resources, valorisation and consumption of fisheries products. The global analysis made here accords a priority to markets as well as to the framework of contribution of these products and tries, at the end of the 20th century, to present some trends. Facing the globalisation phenomena, how will African fisheries producers be challenged in the new millennium? This continental level analysis brings out field application and some different development perspectives for both small scale and industrial fisheries sub-sectors.
    Description: Published
    Keywords: Fisheries
    Repository Name: AquaDocs
    Type: Proceedings Paper , Non-Refereed
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  • 13
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    Ecology. Fish moved by warming waters (2005)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2005-05-14
    Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Inman, Mason -- New York, N.Y. -- Science. 2005 May 13;308(5724):937.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/15890852" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; *Climate ; *Ecosystem ; Environment ; Fisheries ; *Fishes ; North Sea ; Population Dynamics ; *Seawater ; Temperature
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Published by American Association for the Advancement of Science (AAAS)
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  • 14
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    Ecology. North Atlantic right whales in crisis (2005)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2005-07-26
    Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Kraus, Scott D -- Brown, Moira W -- Caswell, Hal -- Clark, Christopher W -- Fujiwara, Masami -- Hamilton, Philip K -- Kenney, Robert D -- Knowlton, Amy R -- Landry, Scott -- Mayo, Charles A -- McLellan, William A -- Moore, Michael J -- Nowacek, Douglas P -- Pabst, D Ann -- Read, Andrew J -- Rolland, Rosalind M -- New York, N.Y. -- Science. 2005 Jul 22;309(5734):561-2.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Edgerton Research Laboratory, New England Aquarium, Boston, MA 02110-3399, USA. skraus@neaq.org〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/16040692" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Atlantic Ocean ; Ecology ; *Ecosystem ; Environment ; Female ; Fisheries ; Male ; Mortality ; Population Dynamics ; Population Growth ; Public Policy ; Reproduction ; Ships ; *Whales/physiology
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Published by American Association for the Advancement of Science (AAAS)
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  • 15
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    Distributed computing. Grassroots supercomputing (2005)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2005-05-10
    Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Bohannon, John -- New York, N.Y. -- Science. 2005 May 6;308(5723):810.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/15879205" target="_blank"〉PubMed〈/a〉
    Keywords: Astronomical Phenomena ; Astronomy ; Climate ; *Computer Communication Networks ; *Computer Simulation ; *Computing Methodologies ; *Internet ; *Microcomputers ; Protein Folding ; Proteins/chemistry ; Software
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Published by American Association for the Advancement of Science (AAAS)
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  • 16
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    Space and earth sciences. Budget woes greet NASA science chief (2005)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2005-08-20
    Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Lawler, Andrew -- New York, N.Y. -- Science. 2005 Aug 19;309(5738):1165.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/16109854" target="_blank"〉PubMed〈/a〉
    Keywords: Astronomy ; Biological Science Disciplines ; *Budgets ; History, 20th Century ; History, 21st Century ; Research ; United States ; United States National Aeronautics and Space ; Administration/economics/history/*organization & administration
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Published by American Association for the Advancement of Science (AAAS)
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  • 17
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    Global patterns of predator diversity in the open oceans (2005)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2005-07-30
    Description: The open oceans comprise most of the biosphere, yet patterns and trends of species diversity there are enigmatic. Here, we derive worldwide patterns of tuna and billfish diversity over the past 50 years, revealing distinct subtropical "hotspots" that appeared to hold generally for other predators and zooplankton. Diversity was positively correlated with thermal fronts and dissolved oxygen and a nonlinear function of temperature (approximately 25 degrees C optimum). Diversity declined between 10 and 50% in all oceans, a trend that coincided with increased fishing pressure, superimposed on strong El Nino-Southern Oscillation-driven variability across the Pacific. We conclude that predator diversity shows a predictable yet eroding pattern signaling ecosystem-wide changes linked to climate and fishing.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Worm, Boris -- Sandow, Marcel -- Oschlies, Andreas -- Lotze, Heike K -- Myers, Ransom A -- New York, N.Y. -- Science. 2005 Aug 26;309(5739):1365-9. Epub 2005 Jul 28.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Biology Department, Dalhousie University, Halifax, NS, Canada B3H 4J1. bworm@dal.ca〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/16051749" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; *Biodiversity ; Climate ; *Ecosystem ; Fisheries ; Oceans and Seas ; Oxygen/analysis ; *Perciformes ; Population Density ; *Predatory Behavior ; Regression Analysis ; Seasons ; Temperature ; Time Factors ; *Tuna ; Zooplankton
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Published by American Association for the Advancement of Science (AAAS)
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  • 18
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    Evolution. Vatican astronomer rebuts cardinal's attack on Darwinism (2005)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2005-08-16
    Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Holden, Constance -- New York, N.Y. -- Science. 2005 Aug 12;309(5737):996-7.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/16099953" target="_blank"〉PubMed〈/a〉
    Keywords: Astronomical Phenomena ; Astronomy ; *Biological Evolution ; *Catholicism ; *Religion and Science ; Vatican City
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Published by American Association for the Advancement of Science (AAAS)
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  • 19
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    Team assembly mechanisms determine collaboration network structure and team performance (2005)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2005-04-30
    Description: Agents in creative enterprises are embedded in networks that inspire, support, and evaluate their work. Here, we investigate how the mechanisms by which creative teams self-assemble determine the structure of these collaboration networks. We propose a model for the self-assembly of creative teams that has its basis in three parameters: team size, the fraction of newcomers in new productions, and the tendency of incumbents to repeat previous collaborations. The model suggests that the emergence of a large connected community of practitioners can be described as a phase transition. We find that team assembly mechanisms determine both the structure of the collaboration network and team performance for teams derived from both artistic and scientific fields.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2128751/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2128751/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Guimera, Roger -- Uzzi, Brian -- Spiro, Jarrett -- Amaral, Luis A Nunes -- K25 GM069546-03/GM/NIGMS NIH HHS/ -- New York, N.Y. -- Science. 2005 Apr 29;308(5722):697-702.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Chemical and Biological Engineering, Northwestern University, Evanston, IL 60208, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/15860629" target="_blank"〉PubMed〈/a〉
    Keywords: Astronomical Phenomena ; Astronomy ; Behavior ; *Cooperative Behavior ; *Creativity ; *Drama ; Ecology ; Economics ; Humans ; *Models, Organizational ; Music ; Psychology, Social ; Publishing ; *Research
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
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  • 20
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    Edward Ames profile. Uncovering the hidden paths of Maine's threatened cod (2005)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2005-11-19
    Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Bhattacharjee, Yudhijit -- New York, N.Y. -- Science. 2005 Nov 18;310(5751):1110-1.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/16293737" target="_blank"〉PubMed〈/a〉
    Keywords: Animal Migration ; Animals ; Conservation of Natural Resources/*history ; Fisheries ; *Gadus morhua/physiology ; History, 20th Century ; History, 21st Century ; Maine ; Public Policy ; Reproduction
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Published by American Association for the Advancement of Science (AAAS)
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  • 21
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    Bilateral action for right whales (2005)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2005-12-13
    Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Sayles, Jesse S -- Green, David M -- New York, N.Y. -- Science. 2005 Dec 9;310(5754):1616-8; author reply 1616-8.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/16339430" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Atlantic Ocean ; Canada ; *Ecosystem ; Environment ; Fisheries ; *International Cooperation ; Mortality ; Population Dynamics ; Public Policy ; Ships ; United States ; *Whales
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Published by American Association for the Advancement of Science (AAAS)
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  • 22
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    Trophic cascades in a formerly cod-dominated ecosystem (2005)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2005-06-11
    Description: Removal of top predators from ecosystems can result in cascading effects through the trophic levels below, completely restructuring the food web. Cascades have been observed in small-scale or simple food webs, but not in large, complex, open-ocean ecosystems. Using data spanning many decades from a once cod-dominated northwest Atlantic ecosystem, we demonstrate a trophic cascade in a large marine ecosystem. Several cod stocks in other geographic areas have also collapsed without recovery, suggesting the existence of trophic cascades in these systems.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Frank, Kenneth T -- Petrie, Brian -- Choi, Jae S -- Leggett, William C -- New York, N.Y. -- Science. 2005 Jun 10;308(5728):1621-3.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Fisheries and Oceans, Bedford Institute of Oceanography, Ocean Sciences Division, Post Office Box 1006, Dartmouth, Nova Scotia, B2Y 4A2, Canada. frankk@mar.dfo-mpo.gc.ca〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/15947186" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Atlantic Ocean ; Biodiversity ; Biomass ; *Ecosystem ; Fisheries ; *Fishes ; *Food Chain ; Gadus morhua ; *Invertebrates ; *Phytoplankton ; Population Density ; Population Dynamics ; Predatory Behavior ; Principal Component Analysis ; Seals, Earless ; *Seawater ; Time Factors ; *Zooplankton
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
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    Breakthrough of the year: the runners-up (2005)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2005-12-24
    Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉New York, N.Y. -- Science. 2005 Dec 23;310(5756):1880-5.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/16373539" target="_blank"〉PubMed〈/a〉
    Keywords: Astronomical Phenomena ; Astronomy ; Biology ; Brain/growth & development ; Brain Diseases/genetics ; Climate ; Earth (Planet) ; Evolution, Planetary ; Humans ; Nuclear Reactors ; Plant Development ; Plants/genetics ; Potassium Channels ; *Research ; Systems Theory
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
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    The onset of planet formation in brown dwarf disks (2005)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2005-10-22
    Description: The onset of planet formation in protoplanetary disks is marked by the growth and crystallization of sub-micrometer-sized dust grains accompanied by dust settling toward the disk mid-plane. Here, we present infrared spectra of disks around brown dwarfs and brown dwarf candidates. We show that all three processes occur in such cool disks in a way similar or identical to that in disks around low- and intermediate-mass stars. These results indicate that the onset of planet formation extends to disks around brown dwarfs, suggesting that planet formation is a robust process occurring in most young circumstellar disks.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Apai, Daniel -- Pascucci, Ilaria -- Bouwman, Jeroen -- Natta, Antonella -- Henning, Thomas -- Dullemond, Cornelis P -- New York, N.Y. -- Science. 2005 Nov 4;310(5749):834-6. Epub 2005 Oct 20.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721, USA. apai@as.arizona.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/16239438" target="_blank"〉PubMed〈/a〉
    Keywords: Astronomical Phenomena ; Astronomy ; Cosmic Dust ; Crystallization ; *Evolution, Planetary ; *Planets ; Spectrum Analysis
    Print ISSN: 0036-8075
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    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
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    Ecosystem management. California tries to connect its scattered marine reserves (2005)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2005-04-23
    Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Avasthi, Amitabh -- New York, N.Y. -- Science. 2005 Apr 22;308(5721):487-8.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/15845821" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; *Biodiversity ; California ; *Conservation of Natural Resources ; *Ecosystem ; Environment ; Fisheries ; *Fishes ; Marine Biology ; *Seawater
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
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    Jellyfish blooms in the Yangtze Estuary (2005)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2005-01-08
    Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Xian, Weiwei -- Kang, Bin -- Liu, Ruiyu -- New York, N.Y. -- Science. 2005 Jan 7;307(5706):41.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/15637253" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; China ; *Ecosystem ; Fisheries ; Fishes ; *Rivers ; Scyphozoa/*growth & development ; Seasons ; Seawater
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
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    Ecology. Ecosystem services (2005)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2005-04-02
    Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Stokstad, Erik -- New York, N.Y. -- Science. 2005 Apr 1;308(5718):41-3.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/15802579" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Biodiversity ; Conservation of Natural Resources ; Costs and Cost Analysis ; Developed Countries ; Developing Countries ; *Ecology/methods ; *Ecosystem ; *Environment ; Eutrophication ; Fisheries ; Humans ; International Cooperation ; Poverty ; Public Policy ; Trees
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
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    Science in Iran. Attack of the killer jellies (2005)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2005-09-17
    Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Stone, Richard -- New York, N.Y. -- Science. 2005 Sep 16;309(5742):1805-6.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/16166491" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Biomass ; *Ctenophora/growth & development/physiology ; *Ecosystem ; Feeding Behavior ; Fisheries ; Fishes ; Food Chain ; International Cooperation ; Iran ; Oceans and Seas ; *Pest Control, Biological ; Population Dynamics ; *Zooplankton
    Print ISSN: 0036-8075
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    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
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    Science in Iran. An Islamic science revolution? (2005)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2005-09-17
    Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Stone, Richard -- New York, N.Y. -- Science. 2005 Sep 16;309(5742):1802-4.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/16166490" target="_blank"〉PubMed〈/a〉
    Keywords: Astronomical Phenomena ; Astronomy ; *Biotechnology ; Iran ; *Islam ; Physical Phenomena ; Physics ; Publishing ; *Research ; *Science
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
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    Endangered species. Ban on Beluga caviar points to sturgeon's worldwide decline (2005)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2005-10-08
    Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Pala, Christopher -- New York, N.Y. -- Science. 2005 Oct 7;310(5745):37.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/16210510" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Commerce/*legislation & jurisprudence ; Conservation of Natural Resources/*legislation & jurisprudence ; *Eggs ; Fisheries ; *Fishes ; Internationality ; United States
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
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    Living laboratory in peril (2005)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2005-05-14
    Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Boersma, P Dee -- Vargas, Hernan -- Merlen, Godfrey -- New York, N.Y. -- Science. 2005 May 13;308(5724):925.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/15890846" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; *Biodiversity ; Biological Evolution ; *Conservation of Natural Resources/legislation & jurisprudence ; *Ecosystem ; Ecuador ; Emigration and Immigration/legislation & jurisprudence ; Fisheries ; Humans ; *Population Growth ; Travel
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
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    Climate change and distribution shifts in marine fishes (2005)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2005-05-14
    Description: We show that the distributions of both exploited and nonexploited North Sea fishes have responded markedly to recent increases in sea temperature, with nearly two-thirds of species shifting in mean latitude or depth or both over 25 years. For species with northerly or southerly range margins in the North Sea, half have shown boundary shifts with warming, and all but one shifted northward. Species with shifting distributions have faster life cycles and smaller body sizes than nonshifting species. Further temperature rises are likely to have profound impacts on commercial fisheries through continued shifts in distribution and alterations in community interactions.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Perry, Allison L -- Low, Paula J -- Ellis, Jim R -- Reynolds, John D -- New York, N.Y. -- Science. 2005 Jun 24;308(5730):1912-5. Epub 2005 May 12.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Centre for Ecology, Evolution and Conservation, School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK. a.perry@uea.ac.uk〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/15890845" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Body Size ; *Climate ; *Ecosystem ; Environment ; Fisheries ; *Fishes/anatomy & histology/growth & development ; North Sea ; Population Density ; Population Dynamics ; *Seawater ; Temperature ; Time Factors
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
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    Reassessing U.S. coral reefs (2005)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2005-06-18
    Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Grigg, Richard W -- Dollar, Steven J -- New York, N.Y. -- Science. 2005 Jun 17;308(5729):1740-2; author reply 1740-2.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/15961652" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; *Anthozoa ; *Conservation of Natural Resources ; *Ecosystem ; Eukaryota ; Fisheries ; Hawaii ; Population Dynamics ; Seals, Earless ; Turtles ; Water Pollution
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
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    New Active Remote-sensing Capabilities: Laser Ablation Spectrometer and Lidar Atmospheric Species Profile Measurements (2005)
    In:  CASI
    Details
    Publication Date: 2017-10-02
    Description: Introduction: With the anticipated development of high-capacity fission power and electric propulsion for deep-space missions, it will become possible to propose experiments that demand higher power than current technologies (e.g. radioisotope power sources) provide. Jupiter Icy Moons Orbiter (JIMO), the first mission in the Project Prometheus program, will explore the icy moons of Jupiter with a suite of high-capability experiments that take advantage of the high power levels (and indirectly, the high data rates) that fission power affords. This abstract describes two high-capability active-remote-sensing experiments that will be logical candidates for subsequent Prometheus-class missions.
    Keywords: Electronics and Electrical Engineering
    Type: Lunar and Planetary Science XXXVI, Part 4; LPI-Contrib-1234-Pt-4
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    Interstellar PAH in the Laboratory and in Space. What have we Learned from the New Generation of Laboratory and Observational Studies? (2005)
    In:  CASI
    Details
    Publication Date: 2018-06-09
    Description: Polycyclic Aromatic Hydrocarbons (PAHs) are an important and ubiquitous component of carbon-bearing materials in space. PAHs are the best-known candidates to account for the IR emission bands (UIR bands) and PAH spectral features are now being used as new probes of the ISM. PAHs are also thought to be among the carriers of the diffuse interstellar absorption bands (DIBs). In the model dealing with the interstellar spectral features, PAHs are present as a mixture of radicals, ions and neutral species. PAH ionization states reflect the ionization balance of the medium while PAH size, composition, and structure reflect the energetic and chemical history of the medium. A major challenge for laboratory astrophysics is to reproduce (in a realistic way) the physical conditions that exist in the emission and/or absorption interstellar zones. An extensive laboratory program has been developed at NASA Ames to assess the physical and chemical properties of PAHs in such environments and to describe how they influence the radiation and energy balance in space and the interstellar chemistry. In particular, laboratory experiments provide measurements of the spectral characteristics of interstellar PAH analogs from the ultraviolet and visible range to the infrared range for comparison with astronomical data. This paper will focus on the recent progress made in the laboratory to measure the direct absorption spectra of neutral and ionized PAHs in the gas phase in the near-UV and visible range in astrophysically relevant environments. These measurements provide data on PAHs and nanometer-sized particles that can now be directly compared to astronomical observations. The harsh physical conditions of the IS medium - characterized by a low temperature, an absence of collisions and strong VUV radiation fields - are simulated in the laboratory by associating a molecular beam with an ionizing discharge to generate a cold plasma expansion. PAH ions are formed from the neutral precursors in an isolated environment at low temperature (of the order of 100 K). The spectra of neutral and ionized PAHs are measured using the high sensitivity methods of cavity ring down spectroscopy (CRDS). These experiments provide unique information on the spectra of free, cold large carbon molecules and ions in the gas phase. Intrinsic band profiles and band positions of cold gas-phase PAHs can now be measured with high-sensitivity spectroscopy and directly compared to the astronomical data. The electronic bands measured for ionized PAH are found to be intrinsically broad (about 20 cm(sup -1)) while the bands associated with the neutral precursors are narrower (of the order of 2 - 10 cm(sup -1)). The laboratory data are discussed and compared with recent astronomical spectra of large and narrow DIBs and with the spectra of circumstellar environments of selected carbon stars and the implications for the interstellar PAH population are derived. Preliminary results also show that carbon nanoparticles are formed during the short residence time of the precursors in the plasma.
    Keywords: Astronomy
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    A 540-640-GHz High-efficiency Four-anode Frequency Tripler (2005)
    In:  Other Sources
    Details
    Publication Date: 2018-06-11
    Description: We report on the design and performance of a broad-band, high-power 540-640-GHz fix-tuned balanced frequency tripler chip that utilizes four planar Schottky anodes. The suspended strip-line circuit is fabricated with a 12-micron-thick support frame and is mounted in a split waveguide block. The chip is supported by thick beam leads that are also used to provide precise RF grounding. At room temperature, the tripler delivers 0.9-1.8 mW across the band with an estimated efficiency of 4.5%-9%. When cooled to 120 K, the tripler provides 2.0-4.2 mW across the band with an estimated efficiency of 8%-12%.
    Keywords: Electronics and Electrical Engineering
    Type: IEEE Transactions on Microwave Theory and Techniques (ISSN 0018-9480); Volume 53; No. 9; 2835-2843
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    Radar Soundings of the Subsurface of Mars (2005)
    In:  Other Sources
    Details
    Publication Date: 2018-06-11
    Description: The martian subsurface has been probed to kilometer depths by the Mars Advanced Radar for Subsurface and Ionospheric Sounding instrument aboard the Mars Express orbiter. Signals penetrate the polar layered deposits, probably imaging the base of the deposits. Data from the northern lowlands of Chryse Planitia have revealed a shallowly buried quasi-circular structure about 250 kilometers in diameter that is interpreted to be an impact basin. In addition, a planar reflector associated with the basin structure may indicate the presence of a low-loss deposit that is more than 1 kilometer thick.
    Keywords: Astronomy
    Type: Science; Volume 310; No. 5756; 1925-1928
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    Hot-Electron Bolometer Mixers on Silicon-on-Insulator Substrates for Terahertz Frequencies (2005)
    In:  Other Sources
    Details
    Publication Date: 2018-06-11
    Description: A terahertz Hot-Electron Bolometer (HEB) mixer design using device substrates based on Silicon-On-Insulator (SOI) technology is described. This substrate technology allows very thin chips (6 pm) with almost arbitrary shape to be manufactured, so that they can be tightly fitted into a waveguide structure and operated at very high frequencies with only low risk for power leakages and resonance modes. The NbTiN-based bolometers are contacted by gold beam-leads, while other beamleads are used to hold the chip in place in the waveguide test fixture. The initial tests yielded an equivalent receiver noise temperature of 3460 K double-sideband at a local oscillator frequency of 1.462 THz and an intermediate frequency of 1.4 GHz.
    Keywords: Electronics and Electrical Engineering
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    Retrieving Storm Electric Fields From Aircraft Field Mill Data. Part I: Theory (2005)
    In:  CASI
    Details
    Publication Date: 2018-06-12
    Description: It is shown that the problem of retrieving storm electric fields from an aircraft instrumented with several electric field mill sensors can be expressed in terms of a standard Lagrange multiplier optimization problem. The method naturally removes aircraft charge from the retrieval process without having to use a high voltage stinger and linearly combined mill data values. It also allows a variety of user-supplied physical constraints (the so-called side constraints in the theory of Lagrange multipliers). Additionally, this paper introduces a novel way of performing the absolute calibration of an aircraft that has several benefits over conventional analyses. In the new approach, absolute calibration is completed by inspecting the time derivatives of mill and pitch data for a pitch down maneuver performed at high (greater than 1 km) altitude. In Part II of this study, the above methods are tested and then applied to complete a full calibration of a Citation aircraft.
    Keywords: Electronics and Electrical Engineering
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    Unraveling the Origin of Short Gamma-ray Bursts (2005)
    In:  CASI
    Details
    Publication Date: 2018-06-12
    Description: The origin of the short (〈2 s) class of gamma-ray bursts (GRBs) is finally becoming clear after decades of search. The first one localized to a few arcseconds accuracy, GRB 050509B, was found to have a highly probable association with a nearby (z = 0.225) elliptical galaxy. A second one with arcsecond localization, GRB 050709, was also associated with a low redshift (z = 0.16) galaxy. We report here the detection of short GRB 050724 with remarkable properties; in particular, it has low energy gamma-ray emission that lasts for 100 s after the main short pulse, strong early X-ray afterglow, and an unusual lightcurve that rebrightens at 3x10(exp 4) s. A position on the sky accurate to 9 arcsec was determined and provided as a GCN alert to ground-based telescopes within 80 s. A subsequent high-resolution X-ray image provided a sub-arcsec position coincident with ground-based optical and radio observations of the afterglow. Like GRB 050509B, this burst is located off-center in an elliptical galaxy. The energy output of the GRB at the host distance of z = 0.258 is 2-3 orders of magnitude less than for long bursts. The low level of star formation in such galaxies is strong evidence against a collapsar or hypernova origin like that associated with long GRBs. Based on these new data, it is highly probable that short GRBs are produced by the coalescence of orbiting neutron stars (NSs) or black holes (BHs), with some evidence for a NS-BH merger in this burst.
    Keywords: Astronomy
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    Discovery of an Afterglow Extension of the Prompt Phase of Two Gamma Ray Bursts Observed by Swift (2005)
    In:  Other Sources
    Details
    Publication Date: 2018-06-12
    Description: Contemporaneous BAT and XRT observations of two recent well-covered GRBs observed by Swift, GRB 050315 and GRB 050319, show clearly a prompt component of the afterglow emission. The rapid slewing capability of the spacecraft enables X-ray observations immediately after the burst, typically approximately 100 s following the initiation of the prompt gamma-ray phase. By fitting a power law form to the gamma-ray spectrum, we extrapolate the time dependent fluxes measured by the BAT, in the energy band 15 - 350 keV, into the spectral regime observed by the XRT, 0.2 - 10 keV, and examine the functional form of the rate of decay of the two light curves. We find that the BAT and XRT light curves merge to form a unified curve. There is a period of steep decay up to approximately 300 s, followed by a flatter decay. The duration of the steep decay, approximately 100 s in the source frame after correcting for cosmological time dilation, agrees with a theoretical estimate for the deceleration time of the relativistic ejecta as it interacts with circumstellar material. For GRB 050315, the steep decay can be characterized by an exponential form, where T(sub e),(BAT)approximately equal to 24 plus or minus 2 s, and T(sub e)(XRT) approximately equal to 35 plus or minus 2 s. For GRB 050319 a power law decay -d lnf/d lnt = n, where n approximately equal to 3, provides a reasonable fit. The early time X-ray fluxes are consistent with representing the lower energy tail of the prompt emission, and provide our first quantitative measure of the decay of the prompt gamma-ray emission over a large dynamic range. The initial steep decay is expected from the high latitude emission from a curved shell of relativistic plasma illuminated only for a short interval. The overall conclusion is that the prompt phase of GRBs lasts for hundreds of seconds longer than previously thought.
    Keywords: Astronomy
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    Analysis of Piezoelectric Structural Sensors with Emergent Computing Techniques (2005)
    In:  CASI
    Details
    Publication Date: 2018-06-12
    Description: The purpose of this project was to try to interpret the results of some tests that were performed earlier this year and to demonstrate a possible use of emergence in computing to solve IVHM problems. The test data used was collected with piezoelectric sensors to detect mechanical changes in structures. This project team was included of Dr. Doug Ramers and Dr. Abdul Jallob of the Summer Faculty Fellowship Program, Arnaldo Colon-Lopez - a student intern from the University of Puerto Rico of Turabo, and John Lassister and Bob Engberg of the Structural and Dynamics Test Group. The tests were performed by Bob Engberg to compare the performance two types of piezoelectric (piezo) sensors, Pb(Zr(sub 1-1)Ti(sub x))O3, which we will label PZT, and Pb(Zn(sub 1/3)Nb(sub 2/3))O3-PbTiO, which we will label SCP. The tests were conducted under varying temperature and pressure conditions. One set of tests was done by varying water pressure inside an aluminum liner covered with carbon-fiber composite layers (a cylindrical "bottle" with domed ends) and the other by varying temperatures down to cryogenic levels on some specially prepared composite panels. This report discusses the data from the pressure study. The study of the temperature results was not completed in time for this report. The particular sensing done with these piezo sensors is accomplished by the sensor generating an controlled vibration that is transmitted into the structure to which the sensor is attached, and the same sensor then responding to the induced vibration of the structure. There is a relationship between the mechanical impedance of the structure and the resulting electrical impedance produced in the in the piezo sensor. The impedance is also a function of the excitation frequency. Changes in the real part of impendance signature relative to an original reference signature indicate a change in the coupled structure that could be the results of damage or strain. The water pressure tests were conducted by pressurizing the bottle on a test stand, and running sweeps of excitations frequencies for each of the piezo sensors and recording the resulting impedance. The sweeps were limited to 401 points by the available analyzer, and it was decided to perform individual sweeps at five different excitation frequency ranges. The frequency ranges used for the PZTs were different in two of the five ranges from the ranges used for the SCP. The bottles were pressurized to empty (no water), 0psig, 77 psig, 155 psig, 227 psig in nearly uniform increments of about 77psi. One of each of the two types of piezo sensors was fastened on to the bottle surface at two locations: about midway between the ends on cylindrical portion of the bottle and at the very edge of one of the end domes. The data was collected in files by sensor type (2 cases), by location (2 cases), by frequency range (5 cases), and pressure (5cases) to produce 100 data sets of 401 impedances. After familiarization with the piezo sensing technology and obtaining the data, the team developed a set of questions to try to answer regarding the data and made assignments of responsibilities. The next section lists the questions, and the remainder of the report describes the data analysis work performed by Dr. Ramers. This includes a discussion of the data, the approach to answering the question using statistical techniques, the use of an emergent system to investigate the data where statistical techniques were not usable, conclusions regarding the data, and recommendations.
    Keywords: Electronics and Electrical Engineering
    Type: The 2004 NASA Faculty Fellowship Program Research Reports; XXXV-1 - XXXV-17; NASA/CR-2005-213847
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    Carbon nanotube Schottky diodes using Ti-Schottky and Pt-ohmic contacts for high frequency applications (2005)
    In:  Other Sources
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    Publication Date: 2018-06-11
    Description: We have demonstrated Schottky diodes using semiconducting single-walled nanotubes (s-SWNTs) with titanium Schottky and platinum Ohmic contacts for high-frequency applications. The diodes are fabricated using angled evaporation of dissimilar metal contacts over an s-SWNT. The devices demonstrate rectifying behavior with large reverse bias breakdown voltages of greater than 15 V. To decrease the series resistance, multiple SWNTs are grown in parallel in a single device, and the metallic tubes are burnt-out selectively. At low biases these diodes showed ideality factors in the range of 1.5 to 1.9. Modeling of these diodes as direct detectors at room temperature at 2.5 terahertz (THz) frequency indicates noise equivalent powers (NEP) potentially comparable to that of the state-of-the-art gallium arsenide solid-state Schottky diodes, in the range of 10-13 W(square root)xHz.
    Keywords: Electronics and Electrical Engineering
    Type: Nano Letters; Volume 5; no. 7; 1469-1474
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    Future of heterodyne receivers at submillimeter wavelengths (2005)
    In:  Other Sources
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    Publication Date: 2018-06-11
    Description: In this review paper we examine these issues very carefully and describe the novel receivers being designed to make heterodyne instruments more competitive. It will be shown that heterodyne instruments will still have significant roles to play in the near future.
    Keywords: Electronics and Electrical Engineering
    Type: The Joint 30th International Conference on Infrared and Millimeter Waves and 13th International Conference of Terahertz Electronics; Williamsburg, VA; United States
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    Observations in the 1.3 and 1.5 THz atmospheric windows with the Receiver Lab Telescope (2005)
    In:  Other Sources
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    Publication Date: 2018-06-11
    Description: The Receiver Lab Telescope (RLT) is a groundbased terahertz telescope; it is currently the only instrument producing astronomical data between 1 and 2 THz. The capabilities of the RLT have been expanding since observations began in late 2002. Initial observations were limited to the 850 GHz and 1.03 THz windows due to the availability of solid state local oscillators. In the last year we have begun observations with new local oscillators for the 1.3 and 1.5 THz atmospheric windows.
    Keywords: Electronics and Electrical Engineering
    Type: 16th International Symposium on Space Terahertz Technology; Gothenburg; Sweden
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    INTEGRAL Observations of the Be/X-ray binary EX0 2030+375 During Outburst (2005)
    In:  CASI
    Details
    Publication Date: 2018-06-12
    Description: We present a type-I outburst of the high-mass X-ray binary EX0 2030+375, detected during INTEGRAL'S Performance and Verification phase in December 2002 (on-source time about 10(exp 6) seconds). In addition, six more outbursts have been observed during INTEGRAL'S Galactic Plane Scans. X-ray pulsations have been detected with a pulse period of 41.691798 plus or minus 0.000016 s. The X-ray luminosity in the 5-300 keV energy range was 9.7 x 10 (exp 36) erg per second, for a distance of 7.1 kpc. Two unusual features were found in the light curve, with an initial peak before the main outburst and another possible spike after the maximum. RXTE observations confirm only the existence of the initial spike. Although the initial peak appears to be a recurrent feature, the physical mechanisms producing it and the possible second spike are unknown. Moreover, a four-day delay between periastron passage and the peak of the outburst is observed. We present for the first time a 5-300 keV broad-band spectrum of this source. It can be modelled by the sum of a disk black body (kT(sub BB) approximately 8 keV) and either with a power law model with Gamma=2.04 plus or minus 0.11 keV or a Comptonized component (spherical geometry, kT(sub e).=30 keV, tau = 2.64, kT(sub w)=1.5 keV).
    Keywords: Astronomy
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    Low-Luminosity AGN As Analogues of Galactic Black Holes in the Low/Hard State: Evidence from X-Ray Timing of NGC 4258 (2005)
    In:  CASI
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    Publication Date: 2018-06-06
    Description: We present a broadband power spectral density function (PSD) measured from extensive RXTE monitoring data of the low-luminosity AGN NGC 4258, which has an accurate, maser-determined black hole mass of (3.9 plus or minus 0.1) x 10(exp 7) solar mass. We constrain the PSD break time scale to be greater than 4.5 d at greater than 90% confidence, which appears to rule out the possibility that NGC 4258 is an analogue of black hole X-ray binaries (BHXRBs) in the high/soft state. In this sense, the PSD of NGC 4258 is different to that of some more-luminous Seyferts, which appear similar to the PSDs of high/soft state X-ray binaries. This result supports previous analogies between LLAGN and X-ray binaries in the low/hard state based on spectral energy distributions, indicating that the AGN/BHXRB analogy is valid across a broad range of accretion rates.
    Keywords: Astronomy
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    XMM-Newton Archival Study of the ULX Population in Nearby Galaxies (2005)
    In:  CASI
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    Publication Date: 2018-06-06
    Description: We have conducted an archival XMM-Newton study of the bright X-ray point sources in 32 nearby galaxies. From our list of approximately 100 point sources, we attempt to determine if there is a low-state counterpart to the Ultraluminous X-ray (ULX) population. Indeed, 16 sources in our sample match the criteria we set for a low-state ULX, namely, L(sub X) greater than 10(exp 38 ergs per second) and a spectrum best fit with an absorbed power law. Further, we find evidence for 26 high-state ULXs which are best fit by a combined blackbody and a power law. As in Galactic black hole systems, the spectral indices, GAMMA, of the low-state objects, as well a s the luminosities, tend to be lower than those of the high-state objects. The observed range of blackbody temperatures is 0.1-1 keV with the most luminous systems tending toward the lowest temperatures. We also find a class of object whose properties (luminosity, blackbody temperature, and power law slopes) are very similar to those of galactic stellar mass black holes. In addition, we find a subset of these objects that can be best fit by a Comptonized spectrum similar to that used for Galactic black holes in the very high state, when they are radiating near the Eddington limit.
    Keywords: Astronomy
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    How to Distinguish Neutron Star and Black Hole X-ray Binaries? Spectral Index and Quasi-Periodic Oscillation Frequency Correlation (2005)
    In:  CASI
    Details
    Publication Date: 2018-06-06
    Description: Recent studies have revealed strong correlations between 1-10 Hz frequencies of quasiperiodic oscillations (QPOs) and the spectral power law index of several Black Hole (BH) candidate sources when seen in the low/hard state, the steep power-law (soft) state, and in transition between these states. In the soft state these index-QPO frequency correlations show a saturation of the photon index GAMMA approximately equal to 2.7 at high values of the low frequency nu(sub L). This saturation effect was previously identified as a black hole signature. In this paper we argue that this saturation does not occur, at least for one neutron star (NS) source 4U 1728-34, for which the index GAMMA monotonically increases with nu(sub L) to the values of 6 and higher. We base this conclusion on our analysis of approximately 1.5 Msec of RXTE archival data for 4U 1728-34. We reveal the spectral evolution of the Comptonized blackbody spectra when the source transitions from the hard to soft states. The hard state spectrum is a typical thermal Comptonization spectrum of the soft photons which originate in the disk and the NS outer photospheric layers. The hard state photon index is GAMMA approximately 2. The soft state spectrum consists of two blackbody components which are only slightly Comptonized. Thus we can claim (as expected from theory) that in NS sources thermal equilibrium is established for the soft state. To the contrary in BH sources, the equilibrium is never established due to the presence of the BH horizon. The emergent BH spectrum, even in the high/soft state, has a power law component. We also identify the low QPO frequency nu(sub L) as a fundamental frequency of the quasi-spherical component of the transition layer (presumably related to the corona and the NS and disk magnetic closed field lines). The lower frequency nu(sub SL) is identified as the frequency of oscillations of a quasi-cylindrical configuration of the TL (presumably related to the NS and disk magnetic open field lines). We also show that the presence of Fe K(sub alpha), emission-line strengths, QPOs, and the link between them does not depend on radio flux in 4U 1728-34.
    Keywords: Astronomy
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    Spreading of thermonuclear flames on the neutron star in SAX J1808.4-3658: an observational tool (2005)
    In:  CASI
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    Publication Date: 2018-06-06
    Description: We analyse archival Rossi X-Ray Timing Explorer (RXTE) proportional counter array (PCA) data of thermonuclear X-ray bursts from the 2002 outburst of the accreting millisecond pulsar SAX 51808.4-3658. We present evidence of a complex frequency modulation of oscillations during burst rise, and correlations among the time evolution of the oscillation frequency, amplitude, and the inferred burning region area. We discuss these findings in the context of a model, based on thermonuclear flame spreading on the neutron star surface, that can qualitatively explain these features. From our model, we infer that for the 2002 Oct. 15 thermonuclear burst, the ignition likely occurred in the mid-latitudes, the burning region took approx. 0.2 s to nearly encircle the equatorial region of the neutron star, and after that the lower amplitude oscillation originated from the remaining asymmetry of the burning front in the same hemisphere where the burst ignited. We emphasize that studies of the evolution of burst oscillation properties during burst rise can provide a powerful tool to understand thermonuclear flame spreading on neutron star surfaces under extreme physical conditions.
    Keywords: Astronomy
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    Detection With Rhessi of High Frequency X-ray Oscillations in the Tail of the 2004 Hyperflare From SGR 1806-20 (2005)
    In:  CASI
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    Publication Date: 2018-06-06
    Description: The recent discovery of high frequency oscillations in giant flares from SGR 1806-20 and SGR 1900+14 may be the first direct detection of vibrations in a neutron star crust. If this interpretation is correct it offers a novel means of testing the neutron star equation of state, crustal breaking strain, and magnetic field configuration. Using timing data from RHESSI, we have confirmed the detection of a 92.5 Hz Quasi-Periodic Oscillation (QPO) in the tail of the SGR 1806-20 giant flare. We also find another, stronger, QPO at higher energies, at 626.5 Hz. Both QPOs are visible only at particular (but different) rotational phases, implying an association with a specific area of the neutron star surface or magnetosphere. At lower frequencies we confirm the detection of an 18 Hz QPO, at the same rotational phase as the 92.5 Hz QPO, and report the additional presence of a broad 26 Hz QPO. We are however unable to make a robust confirmation of the presence of a 30 Hz QPO, despite higher count rates. We discuss our results in the light of neutron star vibration models.
    Keywords: Astronomy
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    Correlative Analysis of GRBs detected by Swift, Konus and HETE (2005)
    In:  CASI
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    Publication Date: 2018-06-06
    Description: Swift has now detected a large enough sample of gamma-ray bursts (GRBs) to allow correlation studies of burst parameters. Such studies of earlier data sets have yielded important results leading to further understanding of burst parameters and classifications. This work focuses on seventeen Swift bursts that have also been detected either by Konus-Wind or HETE-II, providing high energy spectra and fits to E(sub peak). Eight of these bursts have spectroscopic redshifts and for others we can estimate redshifts using the variability/luminosity relationship. We can also compare E(sub peak) with E(sub iso), and for those bursts for which a jet break was observed in the afterglow we can derive E(sub g) and test the relationship between E(peak) and E(sub gamma). For all bursts we can derive durations and hardness ratios from the prompt emission.
    Keywords: Astronomy
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    JPL VLBI Analysis Center IVS Annual Report for 2004 (2005)
    In:  CASI
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    Publication Date: 2018-06-06
    Description: This report describes the activities of the JPL VLBI analysis center for the year 2004. We continue to be celestial reference frame, terrestrial reference frame, earth orientation, and spacecraft navigation work using the VLBI technique. There are several areas of our work that are undergoing active development. In 2004 we demonstrated 1 mm level troposphere calibration on an intercontinental baseline. We detected our first X/Ka (8.4/32 GHz) VLBI fringes. We began to deploy Mark 5 recorders and to interface the Mark 5 units to our software correlator. We also have actively participated in the international VLBI community through our involvement in six papers at the February IVS meeting and by collaborating on a number of projects such as densifying the S/X celestial frame creating celestial frames at K (24 GHz) and Q-bands ($# GHz)〉
    Keywords: Astronomy
    Type: International VLBI Service for Geodesy and Astrometry 2004 Annual Report; 225-228; NASA/TP-2005-212772
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    Bulk Velocities, Chemical Composition and Ionization Structure of the X-ray Shocks in WR140 near Periastron as Revealed by the Chandra Gratings (2005)
    In:  Other Sources
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    Publication Date: 2018-06-06
    Description: The Wolf-Rayet WC7+O4.5 binary WR140 went through the periastron passage of its 8-year eccentric binary orbit in early 2001 as the two stars made their closest approach. Both stars have powerful supersonic stellar winds which crash into each other between the stars to produce X-rays. Chandra grating observations were made when the X-rays were at their brightest making WR140 the brightest hot-star X-ray source in the sky and giving the opportunity to study the velocity profiles of lines, all of which were resolved and blue-shifted. In the general context of shock physics, the measurements constrain the flow of hot gas and where different ions were made. The lower velocity widths of cool ions imply a plasma that was not in equilibrium. The brightness of lines relative to the strong continuum in conjunction with plasma models gives interim abundance estimates for eight different elements in WC-type material including an Ne/S ratio in good agreement with earlier long-wavelength measurements.
    Keywords: Astronomy
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    Viewing the Violent Universe with SWIFT and GLAST (2005)
    In:  CASI
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    Publication Date: 2018-06-06
    Description: As the most energetic form of light, gamma rays help reveal information about some of the most violent phenomena in the Universe. Previous space missions like the Compton Gamma Ray Observatory provided the observations that set the stage for two 21st century gamma-ray programs. Swift, launched in Fall, 2004, concentrates on gamma-ray bursts, the most powerful explosions in the Universe. GLAST, the Gamma-ray Large Area Space Telescope, will be launched in 2007 to study objects like blazars, pulsars, supernovae, and unidentified sources.
    Keywords: Astronomy
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    INTEGRAL/SPI Limits on Electron-Positron Annihilation Radiation from the Galactic Plane (2005)
    In:  CASI
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    Publication Date: 2018-06-06
    Description: The center of our Galaxy is a known strong source of electron-positron 511- keV annihilation radiation. Thus far, however, there have been no reliable detections of annihilation radiation outside of the central radian of our Galaxy. One of the primary objectives of the INTEGRAL (INTErnational Gamma-RAy Astrophysics Laboratory) mission, launched in Oct. 2002, is the detailed study of this radiation. The Spectrometer on INTEGRAL (SPI) is a high resolution coded-aperture gamma-ray telescope with an unprecedented combination of sensitivity, angular resolution and energy resolution. We report results from the first 10 months of observation. During this period a significant fraction of the observing time was spent in or near the Galactic Plane. No positive annihilation flux was detected outside of the central region (|l| greater than 40 degrees) of our Galaxy. In this paper we describe the observations and data analysis methods and give limits on the 511-keV flux.
    Keywords: Astronomy
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    Environmental Influence of Gravity and Pressure on Arc Tracking of Insulated Wires Investigated (2005)
    In:  CASI
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    Publication Date: 2018-06-05
    Description: Momentary short-circuit arcs between a defective polyimide-insulated wire and another conductor may thermally char (pyrolize) the insulating material. The charred polyimide, being conductive, can sustain the short-circuit arc, which may propagate along the wire through continuous pyrolization of the polyimide insulation (arc tracking). If the arcing wire is part of a multiple-wire bundle, the polyimide insulation of other wires within the bundle may become thermally charred and start arc tracking also (flash over). Such arc tracking can lead to complete failure of an entire wire bundle, causing other critical spacecraft or aircraft failures. Unfortunately, all tested candidate wire insulations for aerospace vehicles were susceptible to arc tracking. Therefore, a test procedure was designed at the NASA Lewis Research Center to select the insulation type least susceptible to arc tracking. This test procedure addresses the following three areas of concern: (1) probability of initiation, (2) probability of reinitiation (restrike), and (3) extent of arc tracking damage (propagation rate). Item 2 (restrike probability) is an issue if power can be terminated from and reapplied to the arcing wire (by a switch, fuse, or resettable circuit breaker). The degree of damage from an arcing event (item 3) refers to how easily the arc chars nearby insulation and propagates along the wire pair. Ease of nearby insulation charring can be determined by measuring the rate of arc propagation. Insulation that chars easily will propagate the arc faster than insulation that does not char very easily. A popular polyimide insulated wire for aerospace vehicles, MIL-W-81381, was tested to determine a degree of damage from an arcing event (item 3) in the following three environments: (1) microgravity with air at 1-atm pressure, (2) 1g with air at 1 atm, and (3) 1g within a 10^-6 Torr vacuum. The microgravity 1-atm air was the harshest environment, with respect to the rate of damage of arc tracking, for the 20 AWG (American Wiring Gauge) MIL-W-81381 wire insulation type . The vacuum environment resulted in the least damage. Further testing is planned to determine if the environmental results are consistent between insulation types and to evaluate the other two parameters associated with arc tracking susceptibility.
    Keywords: Electronics and Electrical Engineering
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    Osmium Isotope Evidence for an S-Process Carrier in Primitive Chondrites (2005)
    In:  CASI
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    Publication Date: 2017-10-02
    Description: The degree of isotopic mixing in the solar nebula and the nature of pre-solar components that have contributed to our solar system remain subjects of vigorous debate. Isotopic anomalies have been identified in Ca-Al inclusions in chondrites [1-4]. This indicates that refractory pre-solar components were not completely homogenized or processed away at the high temperatures experienced by CAIs. Pre-solar grains (SiC, C, etc.) are prevalent in primitive chondrites, and preserve isotopic heterogeneity resulting from the nucleosynthetic processes occurring in the stars from which these grains formed [2,4]. Several recent studies employing precise techniques for measuring Ru, Mo and Zr isotopes in bulk meteorites, have come up with varying conclusions on the degree of effectiveness of nebular mixing on the scale of bulk meteorite material. Some of these studies have reported isotopic anomalies in Mo and Ru [3,5-7], while others have not observed anomalies in Mo, Ru, or Zr [8-10]. Debate over the quality of the data, the normalization techniques employed, the absence or presence of isobaric interferences during the measurements on different types of instruments (e.g. TIMS versus ICP-MS), and other factors, has ensued [11,12].
    Keywords: Astronomy
    Type: Lunar and Planetary Science XXXVI, Part 2; LPI-Contrib-1234-Pt-2
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    Impact into Coarse Grained Spheres (2005)
    In:  CASI
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    Publication Date: 2017-10-02
    Description: Several experimental studies [1,2,3] indicate that differences in the grain size of the target relative to the projectile could influence the cratering process. Impacts into coarse sand grains of size comparable to the projectile show some discrepancies with existing relationships for crater growth [e.g. 4]. Similarly, targets of ne grained, uniform in diameter glass spheres show differences in crater depth, transient crater diameter, and volume of ejecta excavated as a function of grain size [2,3]. The purpose of this work is to continue investigating how the relative grain size may influence early time coupling between a projectile and target, with implications for subsequent ejecta excavation and crater growth. In previous efforts we used numerical techniques to focus on the propagation of shock waves in coarse, granular media emphasizing the influence of relative grain size on crater growth, ejecta production, cratering efficiency, target strength, and crater shape [5,6,7]. In this study, we use experimental techniques - in part as a reality check for the numerical studies - to report on how coarse grained targets might influence ejecta excavation and crater shape. This body of work possesses important implications for ejecta excavation and cratering efficiency on asteroids that may possess rubble pile-like structures, and on planets that may possess either pre-fractured surfaces or large-scale heterogeneities in shock impedance.
    Keywords: Astronomy
    Type: Lunar and Planetary Science XXXVI, Part 2; LPI-Contrib-1234-Pt-2
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    Stardust@home: A Massively Distributed Public Search for Interstellar Dust in the Stardust Interstellar Dust Collector (2005)
    In:  CASI
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    Publication Date: 2017-10-02
    Description: In January 2006, the Stardust mission will return the first samples from a solid solar system body beyond the Moon. Stardust was in the news in January 2004, when it encountered comet Wild2 and captured a sample of cometary dust. But Stardust carries an equally important payload: the first samples of contemporary interstellar dust ever collected. Although it is known that interstellar (IS) dust penetrates into the inner solar system [2, 3], to date not even a single contemporary interstellar dust particle has been captured and analyzed in the laboratory. Stardust uses aerogel collectors to capture dust samples. Identification of interstellar dust impacts in the Stardust Interstellar Dust Collector probably cannot be automated, but will require the expertise of the human eye. However, the labor required for visual scanning of the entire collector would exceed the resources of any reasonably-sized research group. We are developing a project to recruit the public in the search for interstellar dust, based in part on the wildly popular SETI@home project, which has five million subscribers. We call the project Stardust@home. Using sophisticated chemical separation techniques, certain types of refractory ancient IS particles (so-called presolar grains) have been isolated from primitive meteorites (e.g., [4] ). Recently, presolar grains have been identified in Interplanetary Dust Particles[6]. Because these grains are not isolated chemically, but are recognized only by their unusual isotopic compositions, they are probably less biased than presolar grains isolated from meteorites. However, it is entirely possible that the typical interstellar dust particle is isotopically solar in composition. The Stardust collection of interstellar dust will be the first truly unbiased one.
    Keywords: Astronomy
    Type: Lunar and Planetary Science XXXVI, Part 21; LPI-Contrib-1234-Pt-21
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    Ion Neutral Mass Spectrometer Measurements from Titan (2005)
    In:  CASI
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    Publication Date: 2017-10-02
    Description: Introduction: The Ion Neutral Mass Spectrometer (INMS) aboard the Cassini orbiter has obtained the first in situ composition measurements of the neutral densities of molecular nitrogen, methane, argon, and a host of stable carbon-nitrile compounds in its first flyby of Titan. The bulk composition and thermal structure of the moon s upper atmosphere do not appear to be changed since the Voyager flyby in 1979. However, the more sensitive techniques provided by modern in-situ mass spectrometry also give evidence for large-spatial-scale large-amplitude atmospheric waves in the upper atmosphere and for a plethora of stable carbon-nitrile compounds above 1174 km. Furthermore, they allow the first direct measurements of isotopes of nitrogen, carbon, and argon, which provide interesting clues about the evolution of the atmosphere. The atmosphere was first accreted as ammonia and ammonia ices from the Saturn sub-nebula. Subsequent photochemistry likely converted the atmosphere into molecular nitrogen. The early atmosphere was 1.5 to 5 times more substantial and was lost via escape over the intervening 4.5 billion years due to the reduced gravity associated with the relatively small mass of Titan. Carbon in the form of methane has continued to outgas over time from the interior with much of it being deposited in the form of complex hydrocarbons on the surface and some of it also being lost to space.
    Keywords: Astronomy
    Type: Lunar and Planetary Science XXXVI, Part 21; LPI-Contrib-1234-Pt-21
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    On the Origin of the Saturnian Satellite System: Did Iapetus Form In-Situ? (2005)
    In:  CASI
    Details
    Publication Date: 2017-10-02
    Description: Current models of planet and satellite formation are marred by our lack of understanding regarding the turbulent state of accretion disks. According to the Rayleigh criterion, Keplerian disks are hydrodynamically stable. Indeed, it has been argued that a carefully designed Taylor Couette experiment shows stability in the case of positive radial gradients in specific angular momentum even for high Reynolds numbers [1], in agreement with numerical simulations which consistently show turbulence decay [2]. Other possible sources of turbulence may fail due to low ionization, may decay as the optical depth decreases due to dust coagulation, may involve unrealistic boundary conditions, or result in limited transport. The difficulty stems not only from the degree of turbulence, but also from the kind of turbulence, and whether it may be characterized by an alpha parameter.
    Keywords: Astronomy
    Type: Lunar and Planetary Science XXXVI, Part 13; LPI-Contrib-1234-Pt-13
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    High-Order Tunable Filters Based on a Chain of Coupled Crystalline Whispering Gallery-Mode Resonators (2005)
    In:  Other Sources
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    Publication Date: 2018-06-11
    Description: We demonstrate experimentally a tunable third-order optical filter fabricated from the three voltage-controlled lithium niobate whispering gallery-mode resonators. The filter operates at 1550 nm with 30-MHz bandwidth and can be electrooptically tuned by 12 GHz in the linear regime with approximately 80-MHz/V tuning rate. With this filter, we have demonstrated 6-dB fiber-to-fiber insertion loss and 30-ns tuning speed, limited by the resonator buildup time.
    Keywords: Electronics and Electrical Engineering
    Type: IEEE Photonics Technology Letters; Volume 17; No. 1; 136-138
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    Lithium-Ion Batteries Being Evaluated for Low-Earth-Orbit Applications (2005)
    In:  CASI
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    Publication Date: 2018-06-05
    Description: The performance characteristics and long-term cycle life of aerospace lithium-ion (Li-ion) batteries in low-Earth-orbit applications are being investigated. A statistically designed test using Li-ion cells from various manufacturers began in September 2004 to study the effects of temperature, end-of-charge voltage, and depth-of-discharge operating conditions on the cycle life and performance of these cells. Performance degradation with cycling is being evaluated, and performance characteristics and failure modes are being modeled statistically. As technology improvements are incorporated into aerospace Li-ion cells, these new designs can be added to the test to evaluate the effect of the design changes on performance and life. Cells from Lithion and Saft have achieved over 2000 cycles under 10 different test condition combinations and are being evaluated. Cells from Mine Safety Appliances (MSA) and modules made up of commercial-off-the-shelf 18650 Li-ion cells connected in series/parallel combinations are scheduled to be added in the summer of 2005. The test conditions include temperatures of 10, 20, and 30 C, end-of-charge voltages of 3.85, 3.95, and 4.05 V, and depth-of-discharges from 20 to 40 percent. The low-Earth-orbit regime consists of a 55 min charge, at a constant-current rate that is 110 percent of the current required to fully recharge the cells in 55 min until the charge voltage limit is reached, and then at a constant voltage for the remaining charge time. Cells are discharged for 35 min at the current required for their particular depth-of-discharge condition. Cells are being evaluated in four-cell series strings with charge voltage limits being applied to individual cells by the use of charge-control units designed and produced at the NASA Glenn Research Center. These charge-control units clamp the individual cell voltages as each cell reaches its end-of-charge voltage limit, and they bypass the excess current from that cell, while allowing the full current flow to the remaining cells in the pack. The goal of this evaluation is to identify conditions and cell designs for Li-ion technology that can achieve more than 30,000 low-Earth-orbit cycles. Testing is being performed at the Naval Surface Warfare Center, Crane Division, in Crane, Indiana.
    Keywords: Electronics and Electrical Engineering
    Type: Research and Technology 2004; NASA/TM-2005-213419
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    The High Energy Spectrum of NGC 4151 (2005)
    In:  CASI
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    Publication Date: 2018-06-06
    Description: We present first INTEGRAL observations of the type 1.5 Seyfert galaxy NGC 4151. Combining several INTEGRAL observations performed during 2003, totaling approximately 400 ksec of exposure time, allow us to study the spectrum in the 3 - 300 keV range. The measurements presented here reveal an overall spectrum from X-rays up to the soft gamma-rays that can be described by an absorbed (N(sub H) approximately equal to 5 x 10(exp 22) per square centimeter) and non-variable thermal component, plus a Fe Kalpha line, and an exponential cutoff occurs at 110 keV, consistent with earlier claims. The Galactic hydrogen column density in the line of sight is N(sub H), Gal approximately equal to 2.1 x 10 (exp 20) per square centimeter. The time resolved analysis shows little variation of the spectral parameters. The comparison with CGRO/OSSE data shows that the same spectral model can be applied over a time span of 15 years, while the flux varied by a factor of 2. Applying a Compton reflection component improves the model fit to the INTEGRAL data. Nonetheless the data available to date cannot significantly confirm or exclude the existence of reflection, nor is a high iron overabundance in the absorber, as had been previously suggested, clearly detectable.
    Keywords: Astronomy
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    Novel intercore-cladding lithium niobate thin film coated MOEMS fiber sensor/modulator (2005)
    In:  Other Sources
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    Publication Date: 2018-06-06
    Description: A MOEMS fiber modulator/sensor is fabricated by depositing a lithium niobate sol-gel thin film between the core and cladding of a fiber preform. The preform is then drawn into 125-micron fibers. Such a MOEMS modulator design is expected to enhance existing lithium niobate undersea acousto-optic sound wave detectors. In our proposed version, the lithium niobate thin film alters the ordinary silica core/cladding boundary conditions such that, when a stress or strain is applied to the fiber, the core light confinement factor changes, leading to modulation of fiber light transmission. Test results of the lithium niobate embedded fiber with a 1550-nm, 4-mW laser source revealed a reduction in light transmission with applied tension. As a comparison, using the same laser source, an ordinary silica core/cladding fiber did not exhibit any reduction in transmitted light when the same strain was applied. Further experimental work and theoretical analysis is ongoing.
    Keywords: Electronics and Electrical Engineering
    Type: J. Microlith., Microfab., Microsyst. (ISSN 1537-1646); Volume 4; No. 4; 1-1 - 1-5
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    Eta Carinae: What We have learned recently with HST/STIS, VLT/UVES and VLTI: What We Might Learn with VLT/VLTI across the 2008/9 Minimum (2005)
    In:  CASI
    Details
    Publication Date: 2018-06-06
    Description: Eta Carinae, the LBV that we have learned to love and hate, has revealed many clues of its character over the past seven years by studies with HST and VLT. Based upon X-Ray, optical and IR observations, Eta Carinae is convincingly a massive binary system that uniquely has major nebular ejecta that are connected with historical outbursts. We have successhlly followed the stellar and nebular changes over the 5.5 year cycle, especially with STIS and RXTE, and across the spectroscopic minimum in 2003.5 with STIS, CHANDRA, RXTE, FUSE, and VLT/UVES. The HST/STIS high spatial resolution, combined with appropriate spectral resolving powers from 1150 to 10300 A, has revealed much about the Central Source and especially the spatially resolved extended stellar atmosphere and the ejecta, known as the Homunculus. Indeed the neutral, dusty outer Homunculus, ejected in the 1840s, envelops the newly discovered ionized Little Homunculus, ejected in the 1890s. In line of sight, multiple hot clumps, both ionized and neutral, are seen in absorption and provide much information on the physical conditions of these massive ejecta. Against the nebular-scattered starlight, wind and nebular absorptions provide views at different angles from line of sight. The VLT/UVES studies from 2002 through 2004 provided very important time-sampled spectra of both the star as seen directly and as seen by the SE lobe viewing the polar region of the star. The VLTI 2.2 micron measures of the central source are consistent with a prolate spheroid with its axis extending along the axis of the Homunculus. This is consistent with the noticeably larger wind mass and higher terminal velocity along the axis of the Homunculus compared to that measured in line of sight at about 45 degrees from the polar axes. We understand the system to be a massive primary with an O or WR companion in a very highly elliptical orbit. The spectroscopic minimum occurs during periastron, when the greatly extended primary atmosphere and wind bottles up the ionizing uv radiation of the companion star. This transient drop in uv photons leads to recombination of much of the wind structure and of the nearby ejecta. Doubly-ionized elements (iron, neon, argon, vanadium) recombine to singly ionized forms and extended structures on the scales of below 0.03 arcseconds to an arcsecond change, appear, or disappear. With the loss of the STIS on HST, ground-based observations, especially with high spatial-resolution facilities, including the VLT and VLTI will be key to further studies across the minimum centered on 2009.0. Now is the time to plan for these studies.
    Keywords: Astronomy
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    James Webb Space Telescope XML Database: From the Beginning to Today (2005)
    In:  CASI
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    Publication Date: 2018-06-06
    Description: The James Webb Space Telescope (JWST) Project has been defining, developing, and exercising the use of a common eXtensible Markup Language (XML) for the command and telemetry (C&T) database structure. JWST is the first large NASA space mission to use XML for databases. The JWST project started developing the concepts for the C&T database in 2002. The database will need to last at least 20 years since it will be used beginning with flight software development, continuing through Observatory integration and test (I&T) and through operations. Also, a database tool kit has been provided to the 18 various flight software development laboratories located in the United States, Europe, and Canada that allows the local users to create their own databases. Recently the JWST Project has been working with the Jet Propulsion Laboratory (JPL) and Object Management Group (OMG) XML Telemetry and Command Exchange (XTCE) personnel to provide all the information needed by JWST and JPL for exchanging database information using a XML standard structure. The lack of standardization requires custom ingest scripts for each ground system segment, increasing the cost of the total system. Providing a non-proprietary standard of the telemetry and command database definition formation will allow dissimilar systems to communicate without the need for expensive mission specific database tools and testing of the systems after the database translation. The various ground system components that would benefit from a standardized database are the telemetry and command systems, archives, simulators, and trending tools. JWST has exchanged the XML database with the Eclipse, EPOCH, ASIST ground systems, Portable spacecraft simulator (PSS), a front-end system, and Integrated Trending and Plotting System (ITPS) successfully. This paper will discuss how JWST decided to use XML, the barriers to a new concept, experiences utilizing the XML structure, exchanging databases with other users, and issues that have been experienced in creating databases for the C&T system.
    Keywords: Astronomy
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    A NON-PRE DOUBLE-PEAKED BURST FROM 4U 1636-536: EVIDENCE FOR BURNING FRONT PROPAGATION (2005)
    In:  CASI
    Details
    Publication Date: 2018-06-06
    Description: We analyse Rossi X-ray Timing Explorer (RXTE) Proportional Counter Array (PCA) data of a double-peaked burst from the low mass X-ray binary (LMXB) 4U 1636-536 that shows no evidence for photospheric radius expansion (PRE). We find that the X-ray emitting area on the star increases with time as the burst progresses, even though the photosphere does not expand. We argue that this is a strong indication of thermonuclear flame spreading on the stellar surface during such bursts. We propose a model for such double-peaked bursts, based on thermonuclear flame spreading, that can qualitatively explain their essential features, as well as the rarity of these bursts.
    Keywords: Astronomy
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    Discovery of Fast X-ray Oscillations During the 1998 Giant Flare from SGR 1900+14 (2005)
    In:  CASI
    Details
    Publication Date: 2018-06-06
    Description: We report the discovery of complex high frequency variability during the August 27, 1998 giant flare from SGR 1900+14 using the Rossi X-ray Timing Explorer (RXTE). We detect an approx. equals 84 Hz oscillation (QPO) during a 1 s interval beginning approximately 1 min after the initial hard spike. The amplitude is energy dependent, reaching a maximum of 26% (rms) for photons above 30 keV, and is not detected below 11 keV, with a 90% confidence upper limit of 14% (rms). Remarkably, additional QPOs are detected in the average power spectrum of data segments centered on the rotational phase at which the 84 Hz signal was detected. Two signals, at 53.5 and 155.1 Hz, are strongly detected, while a third feature at 28 Hz is found with lower significance. These QPOs are not detected at other rotational phases. The phenomenology seen in the SGR 1900+14 flare is similar to that of QPOs recently reported by Israel et al. (2005) from the December 27, 2004 flare from SGR 1806-20, suggesting they may have a common origin, perhaps torsional vibrations of the neutron star crust. Indeed, an association of the four frequencies (in increasing order) found in SGR 1900+14 with l = 2, 4, 7, and 13 toroidal modes appears plausible. We discuss our findings in the context of this model and show that if the stars have similar masses then the magnetic field in SGR 1806-20 must be about twice as large as in SGR 1900+14, broadly consistent with estimates from pulse timing.
    Keywords: Astronomy
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    Evidence for Harmonic Content and Frequency Evolution of Oscillations During the Rising Phase of X-ray Bursts From 4U 1636-536 (2005)
    In:  CASI
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    Publication Date: 2018-06-06
    Description: We report on a study of the evolution of burst oscillation properties during the rising phase of X-ray bursts from 4U 1636-536 observed with the proportional counter array (PCA) on board the Rossi X-Ray Timing Explorer (RXTE) . We present evidence for significant harmonic structure of burst oscillation pulses during the early rising phases of bursts. This is the first such detection in burst rise oscillations, and is very important for constraining neutron star structure parameters and the equation of state models of matter at the core of a neutron star. The detection of harmonic content only during the initial portions of the burst rise is consistent with the theoretical expectation that with time the thermonuclear burning region becomes larger, and hence the fundamental and harmonic amplitudes both diminish. We also find, for the first time from this source, strong evidence of oscillation frequency increase during the burst rise. The timing behavior of harmonic content, amplitude, and frequency of burst rise oscillations may be important in understanding the spreading of thermonuclear flames under the extreme physical conditions on neutron star surfaces.
    Keywords: Astronomy
    Type: The Astrophysical Journal; 634; L157-L160
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    The Formation of CIRs at Stream-Stream Interfaces and Resultant Geomagnetic Activity (2005)
    In:  CASI
    Details
    Publication Date: 2018-06-06
    Description: Corotating interaction regions (CIRs) are regions of compressed plasma formed at the leading edges of corotating high-speed solar wind streams originating in coronal holes as they interact with the preceding slow solar wind. Although particularly prominent features of the solar wind during the declining and minimum phases of the 11-year solar cycle, they may also be present at times of higher solar activity. We describe how CIRs are formed, and their geomagnetic effects, which principally result from brief southward interplanetary magnetic field excursions associated with Alfven waves. Seasonal and long-term variations in these effects are briefly discussed.
    Keywords: Astronomy
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    Chandra X-ray Observation of a Mature Cloud-Shock Interaction in the Bright Eastern Knot of Puppis A (2005)
    In:  CASI
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    Publication Date: 2018-06-06
    Description: We present Chandra X-ray images and spectra of the most prominent cloud-shock interaction region in the Puppis A supernova remnant. The Bright Eastern Knot (BEK) has two main morphological components: (1) a bright compact knot that lies directly behind the apex of an indentation in the eastern X-ray boundary and (2) lying 1 westward behind the shock, a curved vertical structure (bar) that is separated from a smaller bright cloud (cap) by faint diffuse emission. Based on hardness images and spectra, we identify the bar and cap as a single shocked interstellar cloud. Its morphology strongly resembles the "voided sphere" structures seen at late times in Klein et al. experimental simulat.ions of cloud-shock interactions, when the crushing of the cloud by shear instabilities is well underway. We infer an intera.ction time of roughly cloud-crushing timescales, which translates to 2000-4000 years, based on the X-ray temperature, physical size, and estimated expansion of the shocked cloud. This is the first X-ray identified example of a cloud-shock interaction in this advanced phase. Closer t o the shock front, the X-ray emission of the compact knot in the eastern part of the BEK region implies a recent interaction with relatively denser gas, some of which lies in front of the remnant. The complex spatial relationship of the X-ray emission of the compact knot to optical [O III] emission suggests that there are multiple cloud interactions occurring along the line of sight.
    Keywords: Astronomy
    Type: The Astrophysical Journal; Volume 1
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    Discovery of an Afterglow Extension of the Prompt Phase of Two Gamma Ray Bursts Observed by Swift (2005)
    In:  CASI
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    Publication Date: 2018-06-06
    Description: Contemporaneous BAT and XRT observations of two recent well-covered GRBs observed by Swift, GRB 050315 and GRB 050319, show clearly a prompt component joining the onset of the afterglow emission. The rapid slewing capability of the spacecraft enables X-ray observations immediately after the burst, typically ~ 100 s following the initiation of the prompt y-ray phase. By fitting a power law form to the y-ray spectrum, we extrapolate the time dependent fluxes measured by the BAT, in the energy band 15 - 350 keV, into the spectral regime observed by the XRT 0.2 - 10 keV, and examine the functional form of the rate of decay of the two light curves. We find that the BAT and XRT light curves merge to form a unified curve. There is a period of steep decay up to ~ 300 s, followed by a flatter decay. The duration of the steep decay, ~ 100 s in the source frame after correcting for cosmological time dilation, agrees roughly with a theoretical estimate for the deceleration time of the relativistic ejecta as it interacts with circumstellar material. For GRB 050315, the steep decay can be characterized by an exponential form, where one e-folding decay time Te (BAT)~ = 24 f 2 s, and Te,(XRT)~ = 35 f 2 s. For GRB 050319, a power law decay - d l n f / d l n t = n, where n approx. ~ = 3, provides a reasonable fit. The early time X-ray fluxes are consistent with representing the lower energy tail of the prompt emission, and provide our first quantitative measure of the decay of the prompt y-ray emission over a large dynamic range in flux. The initial steep decay is expected due to the delayed high latitude photons from a curved shell of relativistic plasma illuminated only for a short interval. The overall conclusion is that the prompt phase of GRBs remains observable for hundreds of seconds longer than previously thought.
    Keywords: Astronomy
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    Optical and X-ray studies of chromospherically active stars: FR Cancri, HD 95559 and LO Pegasi (2005)
    In:  CASI
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    Publication Date: 2018-06-06
    Description: We present a multiwavelength study of three chromospherically active stars, namely FR Cnc (= BD +16 degrees 1753), HD 95559 and LO Peg (=BD +22 degrees 4409), including newly obtained optical photometry, (for FR Cnc) low-resolution optical spectroscopy, as well as archival IR and X-ray observations. The BVR photometry carried out during the years 2001 - 2004 has found significant photometric variability to be present in all three stars. For FR Cnc, a photometric period 0.826685 +/- 0.000034 d has been established. The strong variation in the phase and amplitude of the FR Cnc light curves when folded on this period implies the presence of evolving and migrating spots or spot groups on its surface. Two independent spots with migration periods of 0.97 and 0.93 years respectively are inferred. The photometry of HD 95559 suggests the formation of a spot (group) during the interval of our observations. We infer the existence of two independent spots or groups in the photosphere of LO Peg, one of which has a migration period of 1.12 years. The optical spectroscopy of FR Cnc carried out during 2002-2003, reveals the presence of strong and variable Ca I1 H and K, H(sub beta) and H(sub alpha) emission features indicative of high level of chromospheric activity. The value of 5.3 for the ratio of the excess emission in H(sub alpha) to H(sub beta), EH(sub alpha)/EH(sub beta), suggests that the chromospheric emission may arise from an extended off-limb region. We have searched for the presence of color excesses in the near-IR JHK bands of these stars using 2MASS data, but none of them appear to have any significant color excess. We have also analyzed archival X-ray observations of HD 95559 and LO Peg carried out by with the ROSAT observatory. The best fit models to their X-ray spectra imply the presence of two coronal plasma components of differing temperatures and with sub-solar metal abundances. The inferred emission measures and temperatures of these systems are similar to those found for other active dwarf stars. The kinematics of FR Cnc suggest that it is a very young (35 - 55 Myrs) main-sequence star and a possible member of the IC 2391 supercluster. LO Peg also has young disk-type kinematics and has been previously suggested to be a member of the 100 Mys old Local Association (Pleiades Moving Group). The kinematics of HD 95559 indicate it is a possible member of the 600 Myrs old Hyades supercluster.
    Keywords: Astronomy
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    Eyewitness Reports of the Great Auroral Storm of 1859 (2005)
    In:  CASI
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    Publication Date: 2018-06-06
    Description: The great geomagnetic storm of 1859 is really composed of two closely spaced massive worldwide auroral events. The first event began on August 28th and the second began on September 2nd. It is the storm on September 2nd that results from the Carrington-Hodgson white light flare that occurred on the sun September l&. In addition to published scientific measurements; newspapers, ship logs and other records of that era provide an untapped wealth of first hand observations giving time and location along with reports of the auroral forms and colors. At its height, the aurora was described as a blood or deep crimson red that was so bright that one "could read a newspaper by." Several important aspects of this great geomagnetic storm are simply phenomenal. Auroral forms of all types and colors were observed to latitudes of 25deg and lower. A significant portion of the world's 125,000 miles of telegraph lines were also adversely affected. Many of - which were unusable for 8 hours or more and had a small but notable economic impact. T h s paper presents only a select few available first hand accounts of the Great Auroral Event of 1859 in an attempt to give the modern reader a sense of how this spectacular display was received by the public from many places around the globe and present some other important historical aspects of the storm.
    Keywords: Astronomy
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    Mission Functionality for Deflecting Earth-Crossing Asteroids/Comets (2005)
    In:  CASI
    Details
    Publication Date: 2018-06-11
    Description: Using astrometric interferometry on near-Earth objects (NEOs) poses many interesting and difficult challenges. Poor reflectance properties and potentially no significant active emissions lead to NEOs having intrinsically low visual magnitudes. Using worst case estimates for signal reflection properties leads to NEOs having visual magnitudes of 27 and higher. Today the most sensitive interferometers in operation have limiting magnitudes of 20 or less. The main reason for this limit is due to the atmosphere, where turbulence affects the light coming from the target, limiting the sensitivity of the interferometer. In this analysis, the interferometer designs assume no atmosphere, meaning they would be placed at a location somewhere in space. Interferometer configurations and operational uncertainties are looked at in order to parameterize the requirements necessary to achieve measurements of low visual magnitude NEOs. This analysis provides a preliminary estimate of what will be required in order to take high resolution measurements of these objects using interferometry techniques.
    Keywords: Astronomy
    Type: Comet/Asteroid Protection System (CAPS): Preliminary Space-Based Concept and Study Results; 121-147; NASA/TM-2005-213758
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    Near-Earth Object Astrometric Interferometry (2005)
    In:  CASI
    Details
    Publication Date: 2018-06-11
    Description: Using astrometric interferometry on near-Earth objects (NEOs) poses many interesting and difficult challenges. Poor reflectance properties and potentially no significant active emissions lead to NEOs having intrinsically low visual magnitudes. Using worst case estimates for signal reflection properties leads to NEOs having visual magnitudes of 27 and higher. Today the most sensitive interferometers in operation have limiting magnitudes of 20 or less. The main reason for this limit is due to the atmosphere, where turbulence affects the light coming from the target, limiting the sensitivity of the interferometer. In this analysis, the interferometer designs assume no atmosphere, meaning they would be placed at a location somewhere in space. Interferometer configurations and operational uncertainties are looked at in order to parameterize the requirements necessary to achieve measurements of low visual magnitude NEOs. This analysis provides a preliminary estimate of what will be required in order to take high resolution measurements of these objects using interferometry techniques.
    Keywords: Astronomy
    Type: Comet/Asteroid Protection System (CAPS): Preliminary Space-Based Concept and Study Results; 102-120; NASA/TM-2005-213758
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    Keeping a Beat on the Heart (2005)
    In:  CASI
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    Publication Date: 2018-06-06
    Description: Feel the relief of a patient suffering from heart arrhythmia, who is able to return home while having her heart monitored by health professionals 24 hours a day, without the fear that she will miss an important indicator and suffer a fatal heart attack - using technology originally developed to conduct experiments on the Space Shuttle. Approximately 400,000 Americans die every year from sudden heart attacks . Medical research revealed that patterns of electrical activity in the heart can act as predictors of these lethal cardiac events known as arrhythmias. Fortunately, certain arrhythmias such as ventricular fibrillation (loss of regular heartbeat and subsequent loss of function) and ventricular tachycardia (rapid heartbeats), can be detected and appropriately treated. Today, patients at moderate risk of arrhythmias can benefit from technology that would permit long- term continuous monitoring of electrical cardiac rhythms outside the hospital environment in the comfort of their own homes. Medical telemetry systems, also known as telemedicine, are evolving rapidly as wireless communication technology advances, evidenced by the commercial products and research prototypes for remote health monitoring that have appeared in recent years. Wireless systems allow patients to move freely in their home and work environment while being monitored remotely by health care professionals.
    Keywords: Electronics and Electrical Engineering
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    Discovery of a Be/X-Ray Binary Consistent with the Location of GRO J2058+42 (2005)
    In:  CASI
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    Publication Date: 2018-06-12
    Description: GRO J2058+42 is a 195 s transient X-ray pulsar discovered in 1995 with BATSE. In 1996, RXTE located GRO J2058+42 to a 90% confidence error circle with a 4 radius. On 2004 February 20, the region including the error circle was observed with Chandra ACIS-I. No X-ray sources were detected within the error circle; however, two faint sources were detected in the ACIS-I field of view. We obtained optical observations of the brightest object, CXOU J205847.5+414637, which had about 64 X-ray counts and was just 013 outside the error circle. The optical spectrum contains a strong Ha line and corresponds to an inhued object in the Two Micron All Sky Survey catalog, indicating a Be/X-ray binary system. Pulsations were not detected in the Chandra observations, but similar flux variations and distance estimates suggest that CXOU J205847.5+414637 and GRO J2058+42 are the same object. We present results from the Chandra observation, optical observations, new and previously unreported RXTE observations, and a reanalysis of a ROSAT observation.
    Keywords: Astronomy
    Type: The Astrophysical Journal; Volume 622; 1024-1032
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    SEU Performance of TAG Based Flip Flops (2005)
    In:  CASI
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    Publication Date: 2018-06-11
    Description: We describe heavy ion test results for two new SEU tolerant latches based on transition nand gates, one for single rail asynchronous and the other for dual rail synchronous designs, implemented in AMI 0.5microprocess.
    Keywords: Electronics and Electrical Engineering
    Type: Meeting held in Seattle, WA on July 11-15, 2005
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    Technology Development for the Constellation-X Spectroscopy X-Ray Telescope (2005)
    In:  CASI
    Details
    Publication Date: 2019-07-27
    Description: The Constellation-X Spectroscopy X-ray Telescope (SXT) is a large diameter, high throughput, grazing incidence imaging mirror system, designed to perform high sensitivity spectroscopy of cosmic X-ray sources in the 0.2-10.0 keV band. The baseline effective area requirement is -3 m# at 1 keV. The system-level angular-resolution requirement is a 15-arcseconds half-power diameter, with a 5-arcsecond goal. The effective area is attained through a modular design, involving the nesting of many confocal, thin-walled Wolter I mirror segments. Considerable progress has been made in developing thin, thermally formed, glass mirror substrates that meet or better the angular-resolution requirement. Several approaches to mounting and aligning reflector segments into a mirror system are under investigation. We report here on the progress of the SXT technology development program toward reaching the performance goals.
    Keywords: Astronomy
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    Spectroscopy of neutral and ionized PAHs. From laboratory studies to astronomical observations (2005)
    In:  Other Sources
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    Publication Date: 2019-07-18
    Description: Polycyclic Aromatic Hydrocarbons (PAHs) are an important and ubiquitous component of carbon-bearing materials in space. PAHs are the best-known candidates to account for the IR emission bands (UIR bands) and PAH spectral features are now being used as new probes of the ISM. PAHs are also thought to be among the carriers of the diffuse interstellar absorption bands (DIBs). In the model dealing with the interstellar spectral features, PAHs are present as a mixture of radicals, ions and neutral species. PAH ionization states reflect the ionization balance of the medium while PAH size, composition, and structure reflect the energetic and chemical history of the medium. A major challenge for laboratory astrochemistry is to reproduce (in a realistic way) the physical conditions that are associated with the emission and absorption interstellar zones. An extensive laboratory program has been developed at NASA Ames to assess the physical and chemical properties of PAHs in such environments and to describe how they influence the radiation and energy balance in space and the interstellar chemistry. PAHs, neutrals and ions, are expanded through a pulsed discharge nozzle (PDN) and probed with high-sensitivity cavity ringdown spectroscopy (CRDS). These laboratory experiments provide unique information on the spectra of free, cold large carbon molecules and ions in the gas phase from the ultraviolet and visible range to the near-infrared range. Intrinsic band profiles and band positions of cold gas-phase PAHs can now be measured with high-sensitivity spectroscopy and directly compared to the astronomical data. Preliminary conclusions from the comparison of the laboratory data with astronomical observations of interstellar and circumstellar environments will also be discussed.
    Keywords: Astronomy
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    The Second Ring-Moon System of Uranus: Discovery and Dynamics (2005)
    In:  Other Sources
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    Publication Date: 2019-07-18
    Description: Deep exposures of Uranus taken with the Hubble Space Telescope reveal two small moons and two faint rings. All orbit outside of Uranus's previously known (main) ring system, but interior to the large, classical moons. The outer new moon, U XXVI Mab, orbits at roughly twice the radius of the main rings and shares its orbit with a dust ring. The second moon, U XXVII Cupid, orbits just interior to the satellite Belinda. A second ring falls between the orbits of Portia and Rosalind, in a region with no known source bodies. Collectively, these constitute a densely-packed, rapidly varying and possibly unstable dynamica1 system.
    Keywords: Astronomy
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    SOFIA'S Challenge: Scheduling Airborne Astronomy Observations (2005)
    In:  Other Sources
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    Publication Date: 2019-07-18
    Description: The Stratospheric Observatory for Infrared Astronomy (SOFIA) is NASA's next generation airborne astronomical observatory, and will commence operations in 2005. The facility consists of a 747-SP modified to accommodate a 2.5 meter telescope. SOFIA is expected to fly an average of 140 science flights per year over its 20 year lifetime. Depending on the nature of the instrument used during flight, 5-15 observations per flight are expected. The SOFIA telescope is mounted aft of the wings on the port side of the aircraft and is articulated through a range of 20deg to 60deg of elevation. The telescope has minimal lateral flexibility; thus, the aircraft must turn constantly to maintain the telescope's focus on an object during observations. A significant problem in future SOFIA operations is that of scheduling flights in support of observations. Investigators are expected to propose small numbers of observations, and many observations must be grouped together to make up single flights. Flight planning for the previous generation airborne observatory, the Kuiper Airborne Observatory (KAO), was done by hand; planners had to choose takeoff time, observations to perform, and decide on setup-actions (called "dead-legs") to position the aircraft prior to observing. This task frequently required between 6-8 hours to plan one flight The scope of the flight planning problem for supporting GI observations with the anticipated flight rate for SOFIA makes the manual approach for flight planning daunting. In response, we have designed an Automated Flight Planner (AFP) that accepts as input a set of requested observations, designated flight days, weather predictions and fuel limitations, and searches automatically for high-quality flight plans that satisfy all relevant aircraft and astronomer specified constraints. The AFP can generate one candidate flight plan in 5-10 minutes, of computation time, a feat beyond the capabilities of human flight planners. The rate at which the AFP can generate flights enables humans to assess and analyze complex tradeoffs between fuel consumption, estimated science quality and the percentage of scheduled observations. Due to the changing nature of SOFIA scheduling problems, this functionality will play a crucial role in optimizing science and minimizing costs during operations. In the full paper, we will summarize the technical challenges that have been met in order to build this system. These include: design of the search algorithm, design of appropriate heuristics and approximations, and reduction in the size of the search space. We will also describe technical challenges that are currently being addressed, including the extension of the existing approach to handle new solution criteria. Finally, we will describe a variety of cultural challenges that the astronomical community must address in order to successfully use SOFIA, and describe how the AFT can be used to address some of these challenges. Specifically, many of the intended science users are accustomed to using ground-based or space-based observatories; we will identify some differences that arise due to the nature of airborne observatories, and how the AFT can be extended to provide useful services to ease these cultural differences.
    Keywords: Astronomy
    Type: Space Mission Challenge for Information Technology; Jul 17, 2006 - Jul 21, 2006; Pasadena, CA; United States
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    Characteristics Of Ferroelectric Logic Gates Using a Spice-Based Model (2005)
    In:  Other Sources
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    Publication Date: 2019-07-18
    Description: A SPICE-based model of an n-channel ferroelectric field effect transistor has been developed based on both theoretical and empirical data. This model was used to generate the I-V characteristic of several logic gates. The use of ferroelectric field effect transistors in memory circuits is being developed by several organizations. The use of FFETs in other circuits, both analog and digital needs to be better understood. The ability of FFETs to have different characteristics depending on the initial polarization can be used to create logic gates. These gates can have properties not available to standard CMOS logic gates, such as memory, reconfigurability and memory. This paper investigates basic properties of FFET logic gates. It models FFET inverter, NAND gate and multi-input NAND gate. The I-V characteristics of the gates are presented as well as transfer characteristics and timing. The model used is a SPICE-based model developed from empirical data from actual Ferroelectric transistors. It simulates all major characteristics of the ferroelectric transistor, including polarization, hysteresis and decay. Contrasts are made of the differences between FFET logic gates and CMOS logic gates. FFET parameters are varied to show the effect on the overall gate. A recodigurable gate is investigated which is not possible with CMOS circuits. The paper concludes that FFETs can be used in logic gates and have several advantages over standard CMOS gates.
    Keywords: Electronics and Electrical Engineering
    Type: International Meeting on Ferroelectricity; Sep 05, 2005 - Sep 09, 2005; Foz do Iguacu; Brazil
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    The Optical Afterglow of a Short Gamma-ray Burst (2005)
    In:  Other Sources
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    Publication Date: 2019-07-18
    Description: It has long been known that there are two classes of gamma-ray bursts (GRBs), principally distinguished by their durations. The breakthrough in our understanding of long-duration GRBs (greater than 2 seconds in duration), that ultimately linked them with energetic Type Ic supernovae, came about from the discovery of their long-lived X-ray and optical "afterglow", when precise and rapid localizations of the sources could finally be obtained. Recently, X-ray localizations have become available for short (less than 2 seconds in duration) GRBs, a hitherto elusive GRB population, that has evaded optical detection for more than thirty years. Here we report the discovery of transient optical emission (R approximately 23 mag) associated with a short GRB. This first short GRB afterglow is localized with sub-arcsecond accuracy onto the outskirts of a blue dwarf galaxy. Unless the optical and X-ray afterglow arise from different mechanisms our observations 33 h after the GRB suggest that, analogously to long GRBs, we observe synchrotron emission from ultrarelativistic ejecta (ZZZ CAN WE LIMIT GAMMA?). In contrast, we did not detect a bright supernova, as found in most nearby long GRB afterglows, which suggests a different origidstrongly constrain the nature of the short GRB progenitors.
    Keywords: Astronomy
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    Integrated Electron-tunneling Refrigerator and TES Bolometer for Millimeter Wave Astronomy (2005)
    In:  Other Sources
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    Publication Date: 2019-07-18
    Description: We describe progress in the development of a close-packed array of bolometers intended for use in photometric applications at millimeter wavelengths from ground- based telescopes. Each bolometer in the may uses a proximity-effect Transition Edge Sensor (TES) sensing element and each will have integrated Normal-Insulator-Superconductor (NIS) refrigerators to cool the bolometer below the ambient bath temperature. The NIS refrigerators and acoustic-phonon-mode-isolated bolometers are fabricated on silicon. The radiation-absorbing element is mechanically suspended by four legs, whose dimensions are used to control and optimize the thermal conductance of the bolometer. Using the technology developed at NIST, we fabricate NIS refrigerators at the base of each of the suspension legs. The NIS refrigerators remove hot electrons by quantum-mechanical tunneling and are expected to cool the biased (approx.10 pW) bolometers to 〈170 mK while the bolometers are inside a pumped 3He-cooled cryostat operating at approx.280 mK. This significantly lower temperature at the bolometer allows the detectors to approach background-limited performance despite the simple cryogenic system.
    Keywords: Astronomy
    Type: Low Temperature Detector Conference; Jul 31, 2005 - Aug 05, 2005; Tokyo; Japan
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    Temperature Tolerant Evolvable Systems Utilizing FPGA Boards and Bias-Controlled Amplifiers (2005)
    In:  Other Sources
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    Publication Date: 2019-07-18
    Description: Space missions often require radiation and extreme-temperature hardened electronics to survive the harsh environments beyond Earth's atmosphere. Traditional approaches to preserve electronics incorporate shielding, insulation and redundancy at the expense of power and weight. However, a novel way of bypassing these problems is the concept of evolutionary hardware. A reconfigurable device, consisting of several switches interconnected with analog/digital parts, is controlled by an evolutionary processor (EP). When the EP detects degradation in the circuit it sends signals to reconfigure the switches, thus forming a new circuit with the desired output. This concept has been developed since the mid-l990s, but one problem remains-the EP cannot degrade substantially. For this reason, extensive testing at extreme temperatures (-180 to 120 C) has been done on devices found on FPGA boards (taking the role of the EP), such as the Analog to Digital and the Digital to Analog Converter. The EP is used in conjunction with a bias-controlled amplifier and a new prototype relay board, which is interconnected with 6 G4-FETs, a tri-input transistor-like element developed at JPL. The greatest improvements to be made lie in the reconfigurable device, so future design and testing of the G4-FET chip is required.
    Keywords: Electronics and Electrical Engineering
    Type: Summer Student Research Presentations; 38; JPL-Publ-05-07
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    A Perfect View of Vesta: Creating Pointing Observations for the Dawn Spacecraft on Asteroid 4 Vesta (2005)
    In:  Other Sources
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    Publication Date: 2019-07-18
    Description: The Dawn spacecraft has a timely and clever assignment in store. It will take a close look at two intact survivors from the dawn of the solar system (asteroids 4 Vesta and 1 Ceres) to understand more about solar system origin and evolution. To optimize science return, Dawn must make carefully designed observations on approach and in survey orbit, high altitude mapping orbit, and low altitude mapping orbit at each body. In this report, observations outlined in the science plan are modeled using the science opportunity analyzer program for the Vesta encounter. Specifically, I encoded Dawn's flight rules into the program, modeled pointing profiles of the optical instruments (framing camera, visible infrared spectrometer) and mapped their fields of view onto Vesta's surface. Visualization of coverage will provide the science team with information necessary to assess feasibility of alternative observation plans. Dawn launches in summer 2006 and ends its journey in 2016. Instrument observations on Vesta in 2011 will supply detailed information about Vesta's surface and internal structure. These data will be used to analyze the formation and history of the protoplanet and, therefore, complete an important step in understanding the development of our solar system.
    Keywords: Astronomy
    Type: Summer Student Research Presentations; JPL-Publ-05-07
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    What's Going on Around BN (2005)
    In:  Other Sources
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    Publication Date: 2019-07-18
    Description: The Becklin-Neugebauer object, discovered in observations made by Eric Becklin as a graduate student, is the brightest mid-infrared source outside the solar system, and a beacon in the nearest region of massive star formation. Using NICMOS on HST, we have obtained near infrared photometric, spectroscopic, and polarimetric images of the region immediately around BN. These images, with resolutions 〈 -0.2", reveal remarkable morphologies, shock details, new young stellar objects, faint stars with variable intensities, and outflow features. We will summarize these results and inferences regarding the shock properties, illuminating sources of the nebulosity, and IRc sources near BN.
    Keywords: Astronomy
    Type: 40 Years of Infrared Astronomy; Apr 01, 2005 - Apr 02, 2005; Westwood, CA; United States
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    Gamma-ray Bursts: The Prompt Emission (2005)
    In:  Other Sources
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    Publication Date: 2019-07-18
    Description: Gamma-ray bursts are the largest explosions in the Universe. The radiation is thought to come from a hypernova initiated from the collapse of a massive star or perhaps the merger of two compact stars such s neutron stars and/or black holes. Most of the observed energy is radiated as gamma rays, usually lasting from a fraction of a second to several hundred seconds. The energy generation process is usually referred to as the "central engine". Observed properties of this prompt emission, including spectra, time profiles and durations will be discussed. The history of these observations and future GRB spacecraft will also be described.
    Keywords: Astronomy
    Type: AAVSO-HEA3 , The 3rd American Association of Variable Star Obervers High Energy Astrophysics Workshop; Mar 21, 2005; Las Cruces, NM; United States
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    Physics-Based Spectra of Accretion Disks around Black Holes (2005)
    In:  Other Sources
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    Publication Date: 2019-07-18
    Description: The purpose of this grant was to begin the process of deriving the light output of accretion disks around black holes directly from the actual processes that inject heat into the accreting matter, rather than from guessed dependences of heating rate on physical parameters. At JHU, the effort has focussed so far on models of accretion onto "intermediate mass black holes", a possible class of black holes, examples of which may have recently been discovered in nearby galaxies. There, Krolik and his student (Yawei Hui) have computed stellar atmospheres for uniformly-heated disks around this class of black holes. Their models serve two purposes: they are the very first serious attempts to compute the spectrum from accreting black holes in this mass range; and a library of such models can be used later in this program as contrasts for those computed on the basis of real disk dynamics. The output from these local disk calculations has also been successfully coupled to a program that applies the appropriate relativistic transformations and computes photon trajectories in order to predict the spectrum received by observers located at different polar angles. The principal new result of these calculations is the discovery of potentially observable ionization edges of H-like C and O at frequencies near the peak in flux from these objects. Most of the grant money at UCSB was spent on supporting graduate student Shane Davis. In addition. some money was spent on supporting two other students: Ari Socrates (now a Hubble Fellow at Princeton), and Laura Melling. Davis spent the year constructing stellar atmosphere models of accretion disks appropriate for the high/soft (thermal) state of black hole X-ray binaries. As with AGN models published previously by our collaboration with NASA support. our models include a complete general relativistic treatment of both the disk structure and the propagation of photons from the disk to a distant observer. They also include all important continuum opacity sources, including Compton scattering and bound-free opacity from abundant metal species. The principal new result is that bound-free opacity is very significant in altering the continuum spectral shape, resulting for example in quite different "color correction factors" compared to those predicted previously. In addition, the models predict a relationship between luminosity and inner disk temperature that is, for the first time, in accord with that observed. The primary purpose of the grant was to incorporate more realistic accretion disk physics, learned largely from simulations, into such spectral models. The Davis et al. paper includes consideration of a vertical dissipation profile computed from radiation magneto-hydrodynamic simulations of MRI turbulence by N. J. Turner (2004). So long as the disk is effectively thick, such dissipation profiles do not affect the predicted spectrum significantly. (More work needs to be done on these simulations, however.) A potentially more serious issue is that MRI turbulence produces substantial inhomogeneities, as do photon bubble instabilities. These inhomogeneities can affect the spectra by enhancing the effects of absorption opacity over scattering opacity. We have done some preliminary Monte Carlo calculations to explore these effects.
    Keywords: Astronomy
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    Decelerating Flows in TeV Blazars: A Resolution to the BL Lac -- FR I Unification Problem (2005)
    In:  Other Sources
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    Publication Date: 2019-07-18
    Description: TeV emission from BL Lacertae (BL) objects i s commonly modeled as Synchrotron-Self Compton (SSC) radiation from relativistically moving homogeneous plasma blobs. In the context of these models, the blob Lorentz factors needed to reproduce the corrected for absorption by the diffuse IR background (DIRB) TeV emission are large ($\delta \gtrsim 50$). The main reason for this is that stronger beaming eases the problem of the lack of $\sim$ IR-UV synchrotron seed photons needed to produce the de-absorbed $\sim $ few TeV peak of the spectral energy distribution (SED). However, such high Doppler factors are in strong disagreement with the unified scheme, according to which BLs are FR I radio galaxies with their jets closely aligned to the line of sight. Here, motivated by the detection of sub-luminal velocities in the sub-pc scale jets of the best studied TeV blazars, MKN 421 and MKN 501, we examine the possibility that the relativistic flows in the TeV BLs decelerate. In this case, the problem of the missing seed photons is solved because of Upstream Compton (UC) scattering, a process in which the upstream energetic electrons from the fast base of the flow 'see' the synchrotron seed photons produced in the slow part of the flow relativistically beamed. Modest Lorentz factors ($\Gamma \sim 15$), decelerating down to values compatible with the recent radio interferometric observations, reproduce the $\sim $ few TeV peak energy of these sources. Furthermore, such decelerating flows are shown to be in agreement with the BL - FR I unification, naturally reproducing the observed BL/FR I broadband luminosity ratios.
    Keywords: Astronomy
    Type: Blazar Florida Conference; Apr 09, 2005 - Apr 12, 2005; FL; United States
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    Initial Results from the Swift Mission (2005)
    In:  Other Sources
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    Publication Date: 2019-07-18
    Description: Swift is a new observatory to study gamma-ray bursts and their afterglows. Launched in November, 2004, Swift has now completed its activation phase and is detecting about two bursts per week with the Burst Alert Telescope. Swift's other two instruments, X-ray Telescope and Ultra-Violet and Optical Telescope, typically start observing the burst within a few minutes. We report the initial results from the wide range of burst and afterglow characteristics that have been found.
    Keywords: Astronomy
    Type: AAS Meeting; May 30, 2005 - Jun 02, 2005; Minneapolis, MN; United States
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    A Search for Transiting Neptune-Mass Extrasolar Planets in High-Precision Photometry of Solar-Type Stars (2005)
    In:  Other Sources
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    Publication Date: 2019-07-18
    Description: Tennessee State University operates several automatic photometric telescopes (APTs) at Fairborn Observatory in southern Arizona. Four 0.8 m APTs have been dedicated to measuring subtle luminosity variations that accompany magnetic cycles in solar-type stars. Over 1000 program and comparison stars have been observed every clear night in this program for up to 12 years with a precision of approximately 0.0015 mag for a single observation. We have developed a transit-search algorithm, based on fitting a computed transit template for each trial period, and have used it to search our photometric database for transits of unknown companions. Extensive simulations with the APT data have shown that we can reliably recover transits with periods under 10 days as long as the transits have a depth of at least 0.0024 mag, or about 1.6 times the scatter in the photometric observations. Thus, due to our high photometric precision, we are sensitive to transits of possible short-period Neptune-mass planets that likely would have escaped detection by current radial velocity techniques. Our search of the APT data sets for 1087 program and comparison stars revealed no new transiting planets. However, the detection of several unknown grazing eclipsing binaries from among our comparison stars, with eclipse depths of only a few millimags, illustrates the success of our technique. We have used this negative result to place limits on the frequency of Neptune-mass planets in close orbits around solar-type stars in the Sun's vicinity.
    Keywords: Astronomy
    Type: NRI 2005; Apr 10, 2005 - Apr 14, 2005; Boulder, CO; United States
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    Coordinated Broadband Monitoring of Variable X-Ray Sources in NGC 1313 (2005)
    In:  Other Sources
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    Publication Date: 2019-07-18
    Description: The nearby (3.7 Mpc) late-type barred spiral galaxy NGC 1313 contains three ultraluminous X-ray sources (ULXs) that are offset from the center of the galaxy. Two of these have been associated with optical ionized nebulae, and their spectral and variability properties indicate that they contain black holes. The third ULX is SN 1978K, which was the second supernova to be detected and recognized as a supernova from its radio emission, and the first from its X-rays. In this project, we have started a long-term program of X-ray (XMM-Newton), optical (VLT), and radio (ATCA) observations of these and other sources in NGC 1313. This program has been continued through Cycle 3. XMM-Newton observations in cycle 2 consisted of eight 10 ksec priority A monitoring observations between 2003 November 25 and 2004 January 16. The data obtained from these observations have been fully analyzed, and the results have been published in Smith et al. (2004). The results included the identification of the optical counterpart of ULX X-2, and firm upper limits for the radio counterparts of ULXs X-1 and X-2. Previously unknown X-ray spectral variability has been detected in ULXs X-1 and X-2. For SNR 1978K, we were able to extend and refine the X-ray decay light curve. In tandem, we developed a semi-analytical model for the spectral variability of microquasar jets, which will be refined and applied to the combined results from our cycle 2 + 3 observations after the cycle-3 data have been fully analyzed.
    Keywords: Astronomy
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    The Amazing SGR 1806-20 (2005)
    In:  Other Sources
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    Publication Date: 2019-07-18
    Description: On 2004 December 27, the brightest gamma-ray flare ever recorded was detected by several instruments to be coming from the Soft Gamma Repeater SGR 1806-20. The flare even caused an ionospheric disturbance recorded around the globe by ionizing the Earth's upper atmosphere. SGRs belong to a class of slowly spinning (P = approx. 5-12 seconds) neutron stars with extremely high surface magnetic fields, B approx. 10(exp 15) G. The high magnetic fields of these objects were suggested by Duncan & Thompson, who called them "magnetars" to reflect the nature of the energy source that produces their quiescent and flaring X-ray luminosities. Very rarely, magnetars emit giant flares, extreme events with total energies typically approx. 10(exp 44) ergs, at least a factor of 1000 higher than the more frequent, repeating SGR bursts. Previously, only two giant flares have been recorded: from SGR 0526-66 in 1979 and from SGR 1900+14 in 1998. In this letter we report the detection of a very bright but rapidly fading radio afterglow that indicates a moderately relativistic expansion of plasma ejected from the magnetar. The radio afterglow is estimated to be at least 700 times brighter than that of the Aug 27 event, and is consistent with the hypothesis (also suggested by gamma-ray and X-ray data) that it was intrinsically a much more powerful event. I will discuss here the VLA results and their implications for the SGR flare energetics.
    Keywords: Astronomy
    Type: 2005 SWIFT Team Meeting; Mar 01, 2005 - Mar 02, 2005; State College, PA; United States
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    The Swift Gamna-Ray Burst Mission (2005)
    In:  Other Sources
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    Publication Date: 2019-07-18
    Description: Swift is a NASA Explorer mission that will be launched in late 2004. It is a multiwavelength observatory for transient astronomy. The goals of the mission are to determine the origin of gamma-ray bursts and their afterglows and use bursts to probe the early Universe. The mission will also perform a hard x-ray survey at the 1 milliCrab level and will continuously monitor the sky for transients. A wide-field gamma-ray camera will detect more than a hundred GRBs per year to 3 times fainter than BATSE. Sensitive narrow-field X-ray and UV/optical telescopes will be pointed at the burst location in 20 to 70 sec by an autonomously controlled "swift" spacecraft. For each burst, arcsec positions will be determined and optical/UV/X-ray/gamma-ray spectrophotometry performed. The instrumentation is a combination of existing flight-spare hardware and design from XMM and Spectrum-X/JET-X contributed by collaborators in the UK and Italy and development of a coded-aperture camera with a large-area (-0.5 square meter) CdZnTe detector array. The ground station in Malindi is contributed by the Italian Space Agency. Key components of the mission are vigorous follow-up and outreach programs to engage the astronomical community and public in Swift.
    Keywords: Astronomy
    Type: AAS Conference; Jan 01, 2005; San Diego, CA; United States
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    Discovery of a Transition to Global Spin-Up in EXO 2030+375 (2005)
    In:  Other Sources
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    Publication Date: 2019-07-18
    Description: EXO 2030+375, a 42 second transient X-ray pulsar with a Be star companion, has been observed to undergo an outburst at nearly every periastron passage for the last 13.5 years. From 1994 through 2002, the global trend in the pulsar spin frequency was spin-down. Using RXTE data from 2003 September, we have observed a transition to global spin-up in EXO 203G+375. Although the spin frequency observations are sparse, the relative spin-up between 2002 June and 2003 September observations along with an overall brightening of the outbursts since mid 2002 observed with the RXTE ASM accompanied by an increase in density of the disk indicated by infrared magnitudes suggest that the pattern observed with BATSE of a roughly constant spin frequency, followed by spin-up, followed by spin-down is repeating. If so this pattern has approximately an 11 year period, similar to the 15 plus or minus 3 year period derived by Wilson et al. (2002) for the precession period of a one-armed oscillation in the Be disk. If this pattern is indeed repeating, we predict a transition from spin-up to spin-down in 2005.
    Keywords: Astronomy
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