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  • Univ. Berlin  (46)
  • Univ. Potsdam  (34)
  • English  (50)
  • German  (30)
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  • 2020-2023
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  • 2010  (80)
  • 1
    facet.materialart.
    Unknown
    Univ. Potsdam
    Publication Date: 2020-10-07
    Description: Central stars of planetary nebulae are low-mass stars on the brink of their final evolution towards white dwarfs. Because of their surface temperature of above 25,000 K their UV radiation ionizes the surrounding material, which was ejected in an earlier phase of their evolution. Such fluorescent circumstellar gas is called a "Planetary Nebula". About one-tenth of the Galactic central stars are hydrogen-deficient. Generally, the surface of these central stars is a mixture of helium, carbon, and oxygen resulting from partial helium burning. Moreover, most of them have a strong stellar wind, similar to massive Pop-I Wolf-Rayet stars, and are in analogy classified as [WC]. The brackets distinguish the special type from the massive WC stars.
    Description: thesis
    Keywords: 523 ; TEG 000 ; Kosmogonie {Astronomie}
    Language: English
    Type: monograph , publishedVersion
    Format: 102 S.
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  • 2
    Publication Date: 2021-03-29
    Description: The presented thesis describes the observations of the Galactic center Quintuplet cluster, the spectral analysis of the cluster Wolf-Rayet stars of the nitrogen sequence to determine their fundamental stellar parameters, and discusses the obtained results in a general context.The Quintuplet cluster was discovered in one of the first infrared surveys of the Galactic center region (Okuda et al. 1987, 1989) and was observed for this project with the ESO-VLT near-infrared integral field instrument SINFONI-SPIFFI. The subsequent data reduction was performed in parts with a self-written pipeline to obtain flux-calibrated spectra of all objects detected in the imaged field of view ...
    Description: thesis
    Keywords: 523 ; TIC 000 ; THT 800 ; TIE 662 ; Sternhaufen {Astronomie} ; Massenreiche Sterne {Astronomie} ; Struktur der Milchstrasse {Astronomie}
    Language: German
    Type: monograph , publishedVersion
    Format: 115 S.
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  • 3
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    Unknown
    Univ. Potsdam
    Publication Date: 2021-03-29
    Description: Stellar magnetic fields, as a crucial component of star formation and evolution, evade direct observation at least with current and near future instruments. However investigating whether magnetic fields are generated by a dynamo process or represent relics from the formation process, or whether they show a behavior similar to the sun or something very different, it is essential to investigate their structure and temporal evolution. Fortunately nature provides us with the possibility to indirectly observe surface topologies on distant stars by means of Doppler shift and polarization of light, though not without its challenges. Based on the mentioned effects, the so called Zeeman-Doppler Imaging technique is a powerful method to retrieve magnetic fields from rapid rotating stars based on measurements of spectropolarimetric observations in terms of Stokes profiles. In recent years, a large number of stellar magnetic field distributions could be reconstructed by Zeeman-Doppler Imaging (ZDI). However, the implementation of this method often relies on many approximations because, as an inversion method, it entails enormous computational requirements.
    Description: thesis
    Keywords: 523 ; THR 000 ; TEG 000 ; Elektrische und magnetische Felder {Sterne} ; Kosmogonie {Astronomie}
    Language: German
    Type: monograph , publishedVersion
    Format: 107 S.
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  • 4
    Publication Date: 2021-03-29
    Description: This work focuses on the distribution of atomic hydrogen in the exosphere of Saturns̉ moon Titan. This work is based on measurements performed by the Hydrogen Deuterium Absorption Cell (HDAC) aboard the Cassini spacecraft, that should directly determine the D/H ratio from the UV emission of atomic hydrogen and deuterium at 121.567 and 121.533 nm, respectively. HDAC measurements were performed on December 26, 2005 during the ninth Titan flyby of the Cassini orbiter. Unfortunately the amount of deuterium in the absorption cell could not be determined. Thus, the purpose, HDAC was designed for could not be achieved. For this reason, HDAC has performed measurements only once. However, the amount of atomic hydrogen in the absorption cell is well known, hence the data using only the hydrogen cell can be used in order to investigate Titans̉ exosphere. This work aims at simulating the HDAC measurements performed in order to investigate Titan’s exosphere, e.g. to determine the distribution of atomic hydrogen. A model of Titan’s exosphere including atomic hydrogen and methane has been developed and the transfer of solar radiation is calculated in order to simulate the HDAC measurements. The radiative transfer is solved using the Monte Carlo method. For the exospheric model, two different atomic hydrogen density distributions were applied, which determine the distribution in the exosphere by different approaches. Density profiles calculated by both models mainly differ in the lower exosphere ...
    Description: thesis
    Keywords: 523 ; TGG 655 ; Saturnmonde {Astronomie}
    Language: English
    Type: monograph , publishedVersion
    Format: 171 S.
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  • 5
    Publication Date: 2021-03-29
    Description: After the epoch of reionisation the intergalactic medium (IGM) is kept at a high photoionisation level by the cosmic UV background radiation field. Primarily composed of the integrated contribution of quasars and young star forming galaxies, its intensity is subject to spatial and temporal fluctuations. In particular in the vicinity of luminous quasars, the UV radiation intensity grows by several orders of magnitude. Due to an enhanced UV radiation up to a few Mpc from the quasar, the ionised hydrogen fraction significantly increases and becomes visible as a reduced level of absorption in the HI Lyman alpha (Ly-alpha) forest. This phenomenon is known as the proximity effect and it is the main focus of this thesis ...
    Description: thesis
    Keywords: 523 ; TBI 000 ; Ultraviolett-Astronomie
    Language: German
    Type: monograph , publishedVersion
    Format: 94 S.
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  • 6
    Publication Date: 2021-03-29
    Description: This thesis discusses dust formation in binary systems, in particular for binary systems consisting of a Mira like star and a brown dwarf. A Mira-like star is an intermediate mass star in a late stage of their stellar evolution on the Asymptotic Giant Branch (AGB), and a brown dwarf, is a sub-stellar object with a mass below that necessary to maintain hydrogen-burning nuclear fusion reactions in their cores. In their radial pulsating elevated convective atmospheres, Mira-stars often develop strong stellar winds, which are driven by radiation pressure on the dust and lead to a substantial mass-loss of the star. Stellar winds are of central importance for the development of medium-heavy-AGB stars. Also, they are a reliable source for the production of dust particles and heavy elements for the interstellar medium and the chemical evolution of galaxies. In fact, most stars are in binary or multiple star systems.For a complete description of the processes of dust formation in binary star systems it is necessary to study the perturbative influence of a second star in the vicinity of a AGB-star with a strong stellar wind. This endeavour is embedded in a long standing tradition of scientific investigation of dust formation at the Zentrum für Astronomie und Astrophysik (ZAA) at the Technical University of Berlin...
    Description: thesis
    Keywords: 523 ; THT 900 ; TII 900 ; Doppelsterne {Astronomie} ; Interstellarer Staub {Astronomie: Interstellare Materie}
    Language: English
    Type: monograph , publishedVersion
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  • 7
    Publication Date: 2021-03-29
    Description: The first extrasolar planet 51 Peg b around the G-type star has been reported in 1995. The planet with few Jupiter masses orbiting its star very closely was detected by measurement of the oscillation in the radial velocity of the host star. In 1999 the first transit, when the planet is eclipsing the host star, of the extrasolar planet HD209458 b was observed with a small ground based photometric telescope. Ever since, new planets in distant systems are continuously being detected with new high precision instruments from the ground and from space. The department of Extrasolar Planets and Atmospheres at Deutsches Zentrum für Luft- und Raumfahrt, Berlin (DLR) is involved in the detection and characterization of extrasolar planets, through participation in the CoRoT space mission. Furthermore, two ground based photometric telescope systems are operated as a ground based support for the space mission CoRoT, dedicated to asteroseismology and to extrasolar planet search with the help of the transit method. The BEST project consists of two small aperture wide field-of-view photometric telescopes devoted to the search for transiting Jupiter-sized extrasolar planets and to the characterization of variable stars in CoRoT target fields...
    Description: thesis
    Keywords: 523 ; THX 100 ; TJ 900 ; TCE 220 ; Detektionsmethoden {Astronomie: Extrasolare Planetensysteme} ; Einzelne Weltraumprojekte ; Bodenständige UV-, Optische und Infrarotteleskope {Astronomische Instrumente}
    Language: English
    Type: monograph , publishedVersion
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  • 8
    Publication Date: 2021-03-29
    Description: Supernovae are known to be the dominant energy source for driving turbulence in the interstellar medium. Yet, their effect on magnetic field amplification in spiral galaxies is still poorly understood. Analytical models based on the uncorrelated-ensemble approach predicted that any created field will be expelled from the disk before a significant amplification can occur. By means of direct simulations of supernova-driven turbulence, we demonstrate that this is not the case. Accounting for vertical stratification and galactic differential rotation, we find an exponential amplification of the mean field on timescales of 100Myr. The self-consistent numerical verification of such a fast dynamo is highly beneficial in explaining the observed strong magnetic fields in young galaxies. We, furthermore, highlight the importance of rotation in the generation of helicity by showing that a similar mechanism based on Cartesian shear does not lead to a sustained amplification of the mean magnetic field. This finding impressively confirms the classical picture of a dynamo based on cyclonic turbulence ...
    Description: thesis
    Keywords: 523 ; THR 000 ; THU 162 ; Elektrische und magnetische Felder {Sterne} ; Supernovae {Astronomie}
    Language: English
    Type: monograph , publishedVersion
    Format: 109 S.
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  • 9
    Publication Date: 2021-03-29
    Description: The Sun is a star, which due to its proximity has a tremendous influence on Earth. Since its very first days mankind tried to "understand the Sun", and especially in the 20th century science has uncovered many of the Sun's secrets by using high resolution observations and describing the Sun by means of models. As an active star the Sun's activity, as expressed in its magnetic cycle, is closely related to the sunspot numbers. Flares play a special role, because they release large energies on very short time scales. They are correlated with enhanced electromagnetic emissions all over the spectrum. Furthermore, flares are sources of energetic particles. Hard X-ray observations (e.g., by NASA's RHESSI spacecraft) reveal that a large fraction of the energy released during a flare is transferred into the kinetic energy of electrons. However the mechanism that accelerates a large number of electrons to high energies (beyond 20 keV) within fractions of a second is not understood yet.
    Description: thesis
    Keywords: 523 ; TGC 560 ; TGC 440 ; Eruptionen, Flares {Astronomie: Sonne} ; Korpuskelstrahlung {Sonne}
    Language: English
    Type: monograph , publishedVersion
    Format: 122 S.
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  • 10
    Publication Date: 2021-03-29
    Description: Das Antarctic Muon And Neutrino Detector Array (AMANDA) ist ein Cherenkov Detektor, der sich im Gletscher der Antarktis am Südpol befindet. Wir präsentieren die Analyse von Daten, die in den Jahren 2000 bis 2004 gesammelt wurden, die einer effektiven Detektorlaufzeit von 1001 Tagen entsprechen. Die Suche zielt auf den Nachweis von elektomagnetische und hadronische Teilchenschauern, so gennante Kaskaden, die durch Elektron- und Tauneutrinowechselwirkung produziert werden können. Die hadronischen Kaskaden können auch über neutrale Ströme Wechselwirkung von Neutrinos aller Arten produziert werden. Der Kaskadenkanal hat einige Vorteile in der Suche nach einem diffusen Fluss von astrophysikalischen Neutrinos. Durch die gute Energieauflösung des AMANDA Detektors kann man zwischen einem harten astrophysikalische Spektrum und einem weichen atmosphärischen Spektrum unterscheiden. Außerdem ist der atmosphärischen Elektronneutrinos Fluss um eine Gößenordnung kleiner als der atmosphärische Myonneutrinofluss. Der Untergrund von atmosphärischem Myonen aus Luftschauern kann unterdrückt werden, weil diese als Spuren im Detektor erscheinen und leicht zu identifizieren sind...
    Description: thesis
    Keywords: 539.7215 ; 523 ; 550 ; TBN 000 ; TCE 500 ; Neutrino-Astronomie ; Sonstige Instrumente {Astronomische Instrumente}
    Language: English
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  • 11
    Publication Date: 2021-03-29
    Description: Die Arbeit beschreibt die Analyse von Beobachtungen zweier Sonnenflecken in zweidimensionaler Spektro-Polarimetrie. Die Daten wurden mit dem Fabry-Pérot-Interferometer der Universität Göttingen am Vakuum-Turm-Teleskop auf Teneriffa erfasst. Von der aktiven Region NOAA 9516 wurde der volle Stokes-Vektor des polarisierten Lichts in der Absorptionslinie bei 630,249 nm in Einzelaufnahmen beobachtet, und von der aktiven Region NOAA 9036 wurde bei 617,3 nm Wellenlänge eine 90-minütige Zeitserie des zirkular polarisierten Lichts aufgezeichnet. Aus den reduzierten Daten werden Ergebniswerte für Intensität, Geschwindigkeit in Beobachtungsrichtung, magnetische Feldstärke sowie verschiedene weitere Plasmaparameter abgeleitet. Mehrere Ansätze zur Inversion solarer Modellatmosphären werden angewendet und verglichen. Die teilweise erheblichen Fehlereinflüsse werden ausführlich diskutiert. Das Frequenzverhalten der Ergebnisse und Abhängigkeiten nach Ort und Zeit werden mit Hilfe der Fourier- und Wavelet-Transformation weiter analysiert.
    Description: thesis
    Keywords: 523 ; TGC 520 ; TGC 100 ; Sonnenflecken {Astronomie} ; Sonnenbeobachtung {Astronomie}
    Language: German
    Type: monograph , publishedVersion
    Format: 117 S.
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  • 12
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    Unknown
    Univ. Berlin
    Publication Date: 2021-03-29
    Description: Magnetic cataclysmic variables, also called AM Her stars or 'polars', are close binaries with mass transfer (accretion), consisting of a late-type main-sequence star (commonly called secondary)and a more massive white dwarf with a strong magnetic field. The late-type star is losing mass to the white dwarf. The overflowing matter firstly follows a ballistic trajectory and is then captured by the magnetic field of the white dwarf and guided along the field lines onto the white dwarf. The released gravitational energy is radiated away in all wavelength ranges from infra-red to X-ray. The observed light of an AM Her system is composed of the contributions from the stellar components and the contributions of the accretion column and the accretion region on the white dwarf. The last two components are not only depending on the actual mass transfer rate but also from the spatial orientation of the magnetic field. Since the white dwarf is locked in synchronous rotation, this leads to emission that varies with orbital phase. The decomposition of the observed light from an AM Her system makes it possible to analyse the different components within this system...
    Description: thesis
    Keywords: 523 ; THK 000 ; Spektren und Spektroskopie von Sternen {Astronomie}
    Language: English
    Type: monograph , publishedVersion
    Format: 140 S.
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  • 13
    facet.materialart.
    Unknown
    Univ. Potsdam
    Publication Date: 2021-03-29
    Description: The intergalactic medium is kept highly photoionised by the intergalactic UV background radiation field generated by the overall population of quasars and galaxies. In the vicinity of sources of UV photons, such as luminous high-redshift quasars, the UV radiation field is enhanced due to the local source contribution. The higher degree of ionisation is visible as a reduced line density or generally as a decreased level of absorption in the Lyman alpha forest of neutral hydrogen. This so-called proximity effect has been detected with high statistical significance towards luminous quasars. If quasars radiate rather isotropically, background quasar sightlines located near foreground quasars should show a region of decreased Lyman alpha absorption close to the foreground quasar. Despite considerable effort, such a transverse proximity effect has only been detected in a few cases...
    Description: thesis
    Keywords: 523 ; 550 ; TIE 400 ; TIE 900 ; Sonstige Sternensysteme {Astronomie} ; Spektren und Leuchtkraft von Sternsystemen {Astronomie}
    Language: English
    Type: monograph , publishedVersion
    Format: 144 S.
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  • 14
    Publication Date: 2021-03-29
    Description: Giacconi et al. (1962) discovered a diffuse cosmic X-ray background with rocket experiments when they searched for lunar X-ray emission. Later satellite missions found a spectral peak in the cosmic X-ray background at ~30 keV. Imaging X-ray satellites such as ROSAT (1990-1999) were able to resolve up to 80% of the background below 2 keV into single point sources, mainly active galaxies. The cosmic X-ray background is the integration of all accreting super-massive (several million solar masses) black holes in the centre of active galaxies over cosmic time. Synthesis models need further populations of X-ray absorbed active galaxy nuclei (AGN) in order to explain the cosmic X-ray background peak at ~30 keV. Current X-ray missions such as XMM-Newton and Chandra offer the possibility of studying these additional populations...
    Description: thesis
    Keywords: 523 ; 550 ; TBK 000 ; TIE 900 ; Hochenergieastronomie ; Sonstige Sternensysteme {Astronomie}
    Language: English
    Type: monograph , publishedVersion
    Format: 226 S.
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  • 15
    Publication Date: 2021-03-29
    Description: This thesis describes two main projects; the first one is the optimization of a hierarchical search strategy to search for unknown pulsars. This project is divided into two parts; the first part (and the main part) is the semi-coherent hierarchical optimization strategy. The second part is a coherent hierarchical optimization strategy which can be used in a project like Einstein@Home. In both strategies we have found that the 3-stages search is the optimum strategy to search for unknown pulsars. For the second project we have developed a computer software for a coherent Multi-IFO (Interferometer Observatory) search. To validate our software, we have worked on simulated data as well as hardware injected signals of pulsars in the fourth LIGO science run (S4). While with the current sensitivity of our detectors we do not expect to detect any true Gravitational Wave signals in our data, we can still set upper limits on the strength of the gravitational waves signals...
    Description: thesis
    Keywords: 523 ; 550 ; TFA 000 ; Relativistische Astrophysik, Gravitation
    Language: English
    Type: monograph , publishedVersion
    Format: 135 S.
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  • 16
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    Unknown
    Univ. Berlin
    Publication Date: 2021-03-29
    Description: This work covers the dominant aspects of landforms and processes related to the cold-climate (periglacial) and hyperarid environment of Mars and relates the knowledge obtained from terrestrial research to possible Martian analogue landforms. Among the plethora of landforms related to cold-climate environments and subsurface permafrost on Mars, those features have been investigated in detail that are related to the creep of ice and debris at the Martian dichotomy escarpment and the southern-hemispheric impact basins, especially Hellas Planitia, and which have been described controversially as either glacial or periglacial in nature. Structures related to seasonal freeze-thaw cycles on Mars which are generally known as thermal contraction polygons form a second major focus of this work. Research presented on this topic focuses on the northern hemispheric Utopia Planitia area and the south-polar cap of Mars. This work was carried out on the basis of observational and geomorphometrical analyses by utilizing imaging-sensor and topographic data in order to address questions regarding the history, development, and current state of cold-climate landforms on Mars. This work provides new insights with respect to age, composition, source of debris and ice, and the deformational and degradational history of lobate debris aprons and similar landforms. It is shown that processes which led to creep of debris and ice at the northern hemispheric dichotomy boundary are transitional in nature and are not easily categorized using standard definitions commonly used in terrestrial research...
    Description: thesis
    Keywords: 523 ; 550 ; V 600 ; VAR 800 ; TGG 545 ; Grenzgebiete. Beziehungen. Wirkungen. Einflüsse {Geologische Wissenschaften} ; Periglazialerscheinungen ; Marsoberfläche {Astronomie}
    Language: German
    Type: monograph , publishedVersion
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  • 17
    Publication Date: 2021-03-29
    Description: In der vorliegenden Arbeit werden Methoden der Erdsystemanalyse auf die Untersuchung der Habitabilität terrestrischer Exoplaneten angewandt. Mit Hilfe eines parametrisierten Konvektionsmodells für die Erde wird die thermische Evolution von terrestrischen Planeten berechnet. Bei zunehmender Leuchtkraft des Zentralsterns wird über den globalen Karbonat-Silikat-Kreislauf das planetare Klima stabilisiert. Für eine photosynthetisch-aktive Biosphäre, die in einem bestimmten Temperaturbereich bei hinreichender CO2-Konzentration existieren kann, wird eine Überlebenspanne abgeschätzt. Der Abstandsbereich um einen Stern, in dem eine solche Biosphäre produktiv ist, wird als photosynthetisch-aktive habitable Zone (pHZ) definiert und berechnet. Der Zeitpunkt, zu dem die pHZ in einem extrasolaren Planetensystem endgültig verschwindet, ist die maximale Lebenspanne der Biosphäre. Für Supererden, massereiche terrestrische Planeten, ist sie umso länger, je massereicher der Planet ist und umso kürzer, je mehr er mit Kontinenten bedeckt ist. Für Supererden, die keine ausgeprägten Wasser- oder Landwelten sind, skaliert die maximale Lebenspanne mit der Planetenmasse mit einem Exponenten von 0,14. Um K- und M-Sterne ist die Überlebensspanne einer Biosphäre auf einem Planeten immer durch die maximale Lebensspanne bestimmt und nicht durch das Ende der Hauptreihenentwicklung des Zentralsterns limitiert...
    Description: thesis
    Keywords: 523 ; THX 500 ; THX 500 ; Exoplaneten {Astronomie: Extrasolare Planetensysteme}
    Language: German
    Type: monograph , publishedVersion
    Format: 88 S.
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  • 18
    Publication Date: 2021-03-29
    Description: The subject of this work is the physical characterization of asteroids, with an emphasis on the thermal inertia of near-Earth asteroids (NEAs). Thermal inertia governs the Yarkovsky effect, a non-gravitational force which significantly alters the orbits of asteroids up to ~20 km in diameter. Yarkovsky-induced drift is important in the assessment of the impact hazard which NEAs pose to Earth. Yet, very little has previously been known about the thermal inertia of small asteroids including NEAs.Observational and theoretical work is reported. The thermal emission of asteroids has been observed in the mid-infrared (5-35 æm) wavelength range using the Spitzer Space Telescope and the 3.0 m NASA Infrared Telescope Facility, IRTF; techniques have been established to perform IRTF observations remotely from Berlin. A detailed thermophysical model (TPM) has been developed and extensively tested; this is the first detailed TPM shown to be applicable to NEA data.
    Description: thesis
    Keywords: 523 ; 550 ; TGG 900 ; Planetoide {Astronomie}
    Language: English
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  • 19
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 523 ; 550 ; TH0 000 ; THP 000 ; THT 600 ; Asteroseismologie, Oszillation {Sterne} ; Thermodynamische Vorgänge in Sternen {Astronomie} ; Riesensterne {Astronomie}
    Language: English
    Type: monograph , publishedVersion
    Format: 135 S.
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  • 20
    Publication Date: 2021-03-29
    Description: In dieser Doktorarbeit wurden im Rahmen des MAGIC Experimentes neue Datenanalysemethoden implementiert, die sich insbesondere fuer die Analyse von Ereignissen niedriger Gammastrahlungsenergie eignen. Die Methoden konnten erfolgreich in Monte Carlo Studien getestet und auf Beobachtungsdaten des Krebsnebels und der extragalaktischen Gammastrahlungsquelle PG1553+113 angewandt werden. Diese Methoden reichen von ''image cleaning'' Techniken und der Nutzung neuer Bildparameter bis zu fortgeschrittenen g/h-Separations- und Energieabschaetzungsverfahren. Zum ersten Mal wurden die Vorteile von Klassifikations- und Regressionsbaeumen in der Gamma-Astrophysik ausgenutzt, um existierende klassische Methoden zu verbessern. Die Analyse - getestet an Monte Carlo Daten - bewies ihre Zuverlaessigkeit bei der Untersuchung der Gammastrahlungsemission des Krebsnebels, wobei ein hochsignifikanter Exzess im Energiebereich unterhalb 100 GeV in nur 1.7 h nachgewiesen werden konnte. Die Analyse von Daten des BL Lac Objekts PG1553+113 ergab signifikante Exzesse fuer Beobachtungen in den Jahren 2005 und 2006. Das kombinierte alpha-Histogramm zeigt ein Signal mit einer Signifikanz, die 8 sigma ueberschreitet...
    Description: thesis
    Keywords: 523 ; TBK 000 ; THT 200 ; Hochenergieastronomie ; Sterne einzelner Spektralklassen {Astronomie}
    Language: English
    Type: monograph , publishedVersion
    Format: 195 S.
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  • 21
    Publication Date: 2021-03-29
    Description: Our dynamic Sun manifests its activity by different phenomena: from the 11-year cyclic sunspot pattern to the unpredictable and violent explosions in the case of solar flares. During flares, a huge amount of the stored magnetic energy is suddenly released and a substantial part of this energy is carried by the energetic electrons, considered to be the source of the nonthermal radio and X-ray radiation. One of the most important and still open question in solar physics is how the electrons are accelerated up to high energies within (the observed in the radio emission) short time scales. Because the acceleration site is extremely small in spatial extent as well (compared to the solar radius), the electron acceleration is regarded as a local process. The search for localized wave structures in the solar corona that are able to accelerate electrons together with the theoretical and numerical description of the conditions and requirements for this process, is the aim of the dissertation...
    Description: thesis
    Keywords: 523 ; TGC 765 ; Korona {Astronomie: Sonne}
    Language: English
    Type: monograph , publishedVersion
    Format: 109 S.
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  • 22
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    Unknown
    Univ. Potsdam
    Publication Date: 2021-03-29
    Description: Our Solar system contains a large amount of dust, containing valuable information about our close cosmic environment. If created in a planet's system, the particles stay predominantly in its vicinity and can form extended dust envelopes, tori or rings around them. A fascinating example of these complexes are Saturnian rings containing a wide range of particles sizes from house-size objects in the main rings up to micron-sized grains constituting the E ring. Other example are ring systems in general, containing a large fraction of dust or also the putative dust-tori surrounding the planet Mars. The dynamical life'' of such circumplanetary dust populations is the main subject of our study...
    Description: thesis
    Keywords: 523 ; TGL 800 ; Interplanetarer Staub {Astronomie}
    Language: English
    Type: monograph , publishedVersion
    Format: 115, 10 Bl.
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  • 23
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 523 ; TGC 800 ; TGC 800 ; Magnetfelder {Astronomie: Sonne}
    Language: English
    Type: monograph , publishedVersion
    Format: 88 Bl.
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  • 24
    Publication Date: 2021-03-29
    Description: I perform and analyse the first ever calculations of rotating stellar iron core collapse in {3+1} general relativity that start out with presupernova models from stellar evolutionary calculations and include a microphysical finite-temperature nuclear equation of state, an approximate scheme for electron capture during collapse and neutrino pressure effects. Based on the results of these calculations, I obtain the to-date most realistic estimates for the gravitational wave signal from collapse, bounce and the early postbounce phase of core collapse supernovae.
    Description: thesis
    Keywords: 523 ; THU 162 ; TFA 000 ; Supernovae {Astronomie} ; Relativistische Astrophysik, Gravitation
    Language: English
    Type: monograph , publishedVersion
    Format: 291 S
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  • 25
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 523 ; THP 000 ; Thermodynamische Vorgänge in Sternen {Astronomie}
    Language: English
    Type: monograph , publishedVersion
    Format: 76 S.
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  • 26
    facet.materialart.
    Unknown
    Univ. Berlin
    Publication Date: 2021-03-29
    Description: Comets belong to the most pristine objects in the Solar System. The study of comets therefore allows one to put constraints to the physical and chemical conditions in the pre-planetary disc. In this work, a one-dimensional simplified multi-fluid model for the analysis of the chemistry in cometary comae was constructed. This model was used for the study of the formation of the C3 and C2 radicals. For this purpose, radial profiles of the optical emissions of C3 and C2 in comets C/2001 Q4 NEAT, C/2002 T7 LINEAR, and 9P/Tempel 1 at heliocentric distances between 1.0 AU and 1.5 AU were analysed. These profiles were obtained by means of long-slit spectroscopy. A reaction network for the formation of C3 and C2 at larger heliocentric distances (Helbert 2002) was updated and extended. Molecules and radicals were identified for which photodissociation reaction rates have to be further constrained before the formation of C3 and C2 can be understood. As comets of special interest, the comets 67P/Churyumov-Gerasimenko and 9P/Tempel 1 were studied in more detail. Both comets are targets of space missions...
    Description: thesis
    Keywords: 523 ; TGL 200 ; Kometen {Astronomie}
    Language: English
    Type: monograph , publishedVersion
    Format: 227 S.
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  • 27
    Publication Date: 2021-03-29
    Description: Diese Arbeit beschreibt die Verbesserung der Richtungsstabilisierung des Flugzeugteleskops SOFIA. Das Ziel des Flugzeugteleskops SOFIA sind astronomische Beobachtungen im Infrarotbereich. Da der Wasserdampf der Erdatmosphäre den Großteil der Infrarotstrahlung absorbiert, sind solche Beobachtungen mit herkömmlichen Teleskopen von der Erdoberfläche aus kaum möglich. Um unerwünschte Drehbewegungen des Flugzeugteleskops, z.B. hervorgerufen durch Luftturbulenzen, auszugleichen, ist zuerst eine genaue Messung bzw. Schätzung derselben notwendig. Diese Informationen werden dann mittels Computer in Echtzeit weiterverarbeitet. Anschließend sorgen dann Motoren dafür, das Teleskop wieder in die gewünschte Lage zu drehen. Die Motoren können das Teleskop nur so genau ausrichten, wie es die Genauigkeit des Meßsystems zuläßt. Die Messung der Drehbewegungen geschieht mit drei zueinander senkrecht angeordneten Gyroskopen. Diese weisen jedoch Fehler auf, so daß sich die Ausrichtgenauigkeit verschlechtert. Deshalb werden mit Hilfe einer auf das Teleskop montierten Kamera in regelmäßigen Zeitabständen Bilder des Sternhimmels aufgenommen. Aus diesen Bildern wird dann mit Hilfe der dort sichtbaren Sterne die aktuelle Orientierung des Teleskops bestimmt. Mittels dieser Orientierung werden dann die Fehler der Gyroskope korrigiert und der lineare Fehleranteil für die Zukunft extrapoliert. Dieser Fehler wird dann schon im Voraus vom Teleskoplageregler berücksichtigt. Dadurch wird der quasikonstante Fehleranteil minimiert. Je besser dieser Fehler geschätzt wird, desto geringer ist die Drift des Teleskops um seine Achsen. Dadurch erhöht sich die Richtungsstabilisierung ...
    Description: thesis
    Keywords: 522 ; TCE 200 ; Teleskope {Astronomische Instrumente}
    Language: German
    Type: monograph , publishedVersion
    Format: 125 S.
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  • 28
    Publication Date: 2021-03-29
    Description: Bei von Sternen verursachten Mikrolinsen-Ereignissen beobachtet man meist symmetrische Lichtkurven einer einzelnen Linse oder asymmetrische Lichtkurven (oftmals mit Kaustik-Crossing), die durch Doppel-Linsen hervorgerufen werden. Im Prinzip kann aus der Zahl der gemessenen unsymmetrischen Ereignisse der Anteil der Doppelstern-Systeme in Abhängigkeit vom Winkelabstand abgeschätzt werden. Allerdings kann auch ein Doppelsystem Lichtkurven erzeugen, die gut mit einer Einzellinsen-Lichtkurve gefittet werden können. Die gilt insbesondere bei lückenhafter Messung oder grossen Messfehlern. In dieser Arbeit wird für verschiedene Beobachtungsbedingungen untersucht, wie häufig Lichtkurven, die von Doppellinsen mit unterschiedlichen Abständen erzeugt werden, gut mit Einzellinsen-Lichtkurven gefittet werden können und damit fehlinterpretiert werden. Es wurde herausgefunden, dass der Anteil fehlinterpretierter Lichtkurven stark von der Separation der Komponenten abhängig ist: das Minimum liegt zwischen 2 A.E. and 5 A.E. , wobei der Anteil immer noch 5% beträgt...
    Description: thesis
    Keywords: 523 ; THX 100 ; TDC 000 ; Detektionsmethoden {Astronomie: Extrasolare Planetensysteme} ; Astrometrie
    Language: English
    Type: monograph , publishedVersion
    Format: 153 S.
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  • 29
    facet.materialart.
    Unknown
    Univ. Potsdam
    Publication Date: 2021-03-29
    Description: Seit ihrer Entdeckung im Jahre 1610 durch Galileo Galilei faszinieren die Ringe des Saturn sowohl Laien als auch Experten. Planetare Ringe finden sich in der Äquatorialebene aller vier Riesenplaneten unseres Sonnensystems und sind eines der eindruckvollsten Beispiele granularer Gase. Darunter gehören die Saturnringe zu den Bekanntesten. Sie bergen eine Vielzahl von Strukturen und erstrecken sich über mehr als 240 000 Kilometer, wobei sie weit weniger als 100 Meter dick sind. Unzählige kleinerer Körper bewegen sich auf leicht exzentrischen Kepler-ähnlichen Bahnen um den Zentralplaneten und bestehen dabei vorwiegend aus Eis. Die seit Juli 2004 im Orbit um den Saturn befindliche Raumsonde Cassini liefert atemberaubende Bilder und Daten, die nicht nur neue Erkenntnisse liefern, sondern auch alte Fragestellungen neu aufleben lassen. Dazu gehört z.B. die Frage nach dem Ursprung und den Entwicklungsstufen planetarer Ringe. Kürzlich, im äusseren A-Ring entdeckte Kleinmonde, deren Existenz schon viel früher postuliert wurde, weisen auf eventuell stattfindende Wachstumsprozesse hin. Da sich planetare Ringe jedoch hauptsächlich innerhalb der sogenannten Roche-Zone des jeweiligen Planeten befinden, ist ein effektives, allein auf gravitativen Wechselwirkungen beruhendes Größenwachstum nicht zu erwarten. Der Einfluß von Teilchenadhäsion auf diese Prozesse ist bis dato fraglich.
    Description: thesis
    Keywords: 523 ; TGE 590 ; TGG 650 ; Planetenringe {Astronomie} ; Saturn {Astronomie}
    Language: English
    Type: monograph , publishedVersion
    Format: 106 S.
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  • 30
    Publication Date: 2021-03-29
    Description: Die Untersuchung der Oberflächenzusammensetzung von Ganymed basiert auf Daten des abbildenden Spektrometers NIMS an Bord der Raumsonde Galileo, das die Ganymedoberfläche im Spektralbereich des Nahen Infrarot detektiert. Die Verarbeitung der vorliegenden Spektraldaten einschließlich der quantitativen Analyse der spektralen Signaturen in den Reflexionsspektren von Ganymed wie deren Charakterisierung in Abhängigkeit der geologischen Oberflächenstrukturen bildet den zentralen Teil der Arbeit. Die Ergebnisse zeigen, dass Veränderungen der Reflexionseigenschaften der Ganymedoberfläche auf den wechselnden Anteil von Wassereis und Gesteinsmaterial und dem Gehalt an CO2 zurückzuführen sind. Die simultane Analyse der Absorptionen von Wassereis erlaubt es ferner, erstmals Veränderungen des relativen Anteils und der Partikelgröße von Wassereis getrennt voneinander zu erfassen...
    Description: thesis
    Keywords: 523.45 ; 550 ; TGG 605 ; Jupitermonde {Astronomie}
    Language: German
    Type: monograph , publishedVersion
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  • 31
    facet.materialart.
    Unknown
    Univ. Potsdam
    Publication Date: 2021-03-29
    Description: Sterne entstehen im Inneren von turbulenten Molekülwolken, die unter dem Einfluss ihrer eigenen Gravitation fragmentieren und kollabieren. So entsteht ein Sternhaufen aus hundert oder mehr Objekten. Der Sternentstehungsprozess wird durch das Wechselspiel von Überschallturbulenz und Gravitation reguliert. In dieser Arbeit werden verschiedene Eigenschaften solcher Sternhaufen, die mit Hilfe von numerischen Simulationen modelliert wurden, untersucht und mit Beobachtungsdaten verglichen. Dabei handelt es sich sowohl um Eigenschaften einzelner Protosterne, als auch um statistische Parameter des Sternhaufens als Ganzes...
    Description: thesis
    Keywords: 523 ; TIC 000 ; TEG 000 ; Sternhaufen {Astronomie} ; Kosmogonie {Astronomie}
    Language: English
    Type: monograph , publishedVersion
    Format: 138 S.
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  • 32
    facet.materialart.
    Unknown
    Univ. Berlin
    Publication Date: 2021-03-29
    Description: AM Herculis stars (or 'polars') are close binaries consisting of a white dwarf with a strong magnetic field and a main sequence star (the 'secondary') which is losing mass to the white dwarf. The magnetic field channels the matter to the magnetic poles, where the released potential energy is radiated away - mainly in X-rays and the UV. The spatial structure of these objects cannot be observed directly, because their apparent size is too small. Indirect imaging methods are capable of restoring information which is only contained in observational data as projections onto a sub-space. These tomographic methods are known from medicine, but can also be applied to astronomical data, when a number of measurements can be regarded as views of the same object under different aspect angles. In this work tomographic methods are applied to time-resolved spectroscopic data of polars. Spectral lines seen in the radiation emitted by the constituents of these systems are notably Doppler-shifted. The Doppler-shift is depending on the viewing angle of the system ('inclination') and is varying with orbital phase. Time-series of one-dimensional data (spectra) can be used to create a two-dimensional map of the intensity distribution in velocity-space (Doppler-tomography), or a map of the line-flux on the assumed surface of the mass-losing star (Roche-tomography) from the line profile changes ...
    Description: thesis
    Keywords: 523 ; THT 900 ; THU 155 ; Doppelsterne {Astronomie} ; Eruptionsveränderliche {Astronomie: Sterne}
    Language: English
    Type: monograph , publishedVersion
    Format: 124 S.
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  • 33
    Publication Date: 2021-03-29
    Description: The aim of this thesis is to obtain as much information as possible, about global solutions of the Cauchy problem for the Einstein-Vlasov-scalar field system with spherical, plane and hyberbolic symmetries written in areal coordinates. The sources of this system are generated by both a distribution function and a linear scalar field subject to the Vlasov and wave equations respectively. This system describes the evolution of self-gravitating collisionless matter and scalar waves within the context of general relativity. We consider the cosmological case. That is spacetimes possess a compact Cauchy hypersurface and then, data are given on a compact 3-manifold. We extend the local-in-time results obtained by G. Rein for the Einstein-Vlasov system with collisionless matter alone. This extension concerns pointwise estimates for hyperbolic equations by the method of characteristics. This means that the system is transformed to a system of ordinary differential equations which are integrated along characteristics ...
    Description: thesis
    Keywords: 523 ; TFA 000 ; Relativistische Astrophysik, Gravitation
    Language: English
    Type: monograph , publishedVersion
    Format: 85 S.
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  • 34
    facet.materialart.
    Unknown
    Univ. Potsdam
    Publication Date: 2021-03-29
    Description: In dieser Dissertation nutze ich den Gravitationslinseneffekt, um eine Reihe von kosmologischen Fragen zu untersuchen. Der Laufzeitunterschied des Gravitationslinsensystems HE1104-1805 wurde mit unterschiedlichen Methoden bestimmt. Zwischen den beiden Komponenten erhalte ich einen Unterschied von Delta_t(A-B) = -310 +-20 Tagen (2 sigma Konfidenzintervall). Außerdem nutze ich eine dreijährige Beobachtungskampagne, um den Doppelquasar Q0957+561 zu untersuchen. Die beobachteten Fluktuationen in den Differenzlichtkurven lassen sich durch Rauschen erklären, ein Mikrogravitationslinseneffekt wird zur Erklärung nicht benötigt...
    Description: thesis
    Keywords: 523 ; TEG 400 ; TFA 000 ; Endstadien von Sternen {Astronomie: Kosmogonie} ; Relativistische Astrophysik, Gravitation
    Language: English
    Type: monograph , publishedVersion
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  • 35
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 551 ; VBQ 900 ; VBQ 800 ; VEO 170 ; Hydrogeologie einzelner Regionen ; Aquifere {Hydrogeologie} ; Sudan {Geologie}
    Language: English
    Type: monograph , publishedVersion
    Format: 133 S.
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  • 36
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 560 ; VDH 200 ; VEX 100 ; VWH 200 ; VZX 100 ; VKB 380 ; Jura ; Anden {Geologie} ; Jura {Stratigraphische Paläontologie} ; Anden {Paläontologie} ; Sedimente bestimmter Regionen
    Language: German
    Type: monograph , publishedVersion
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  • 37
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 910 ; 551 ; VBQ 900 ; VEB 213 ; VJC 110 ; Hydrogeologie einzelner Regionen ; Brandenburg, Sachsen-Anhalt & Mecklenburg-Vorpommern {Geologie} ; Geochemie des Grundwassers, Porenwassers
    Language: German
    Type: monograph , publishedVersion
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  • 38
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 549 ; VGB 700 ; VGA 300 ; VHB 820 ; Spektroskopische Methoden {Mineralogie} ; Kristallstrukturen ; Inselsilikate {Mineralogie}
    Language: German
    Type: monograph , publishedVersion
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  • 39
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 549 ; VHB 850 ; VGF 200 ; Kettensilikate {Mineralogie} ; Phasengleichgewichte und Umbildungen {Mineralogie}
    Language: English
    Type: monograph , publishedVersion
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  • 40
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 551 ; VQC 000 ; VRA 110 ; VTG 000 ; Lagerstättengenese ; Eisenerz {Lagerstättenkunde} ; Osteuropa und Asiatische Teile der ehemaligen Sowjetrepubliken {Rohstoffgeologie}
    Language: German
    Type: monograph , publishedVersion
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  • 41
    Publication Date: 2021-03-29
    Description: This study presents noble gas compositions (He, Ne, Ar, Kr, and Xe) of lavas from several Hawaiian volcanoes. Lavas from the Hawaii Scientific Drilling Project (HSDP) core, surface samples from Mauna Kea, Mauna Loa, Kilauea, Hualalai, Kohala and Haleakala as well as lavas from a deep well on the summit of Kilauea were investigated ...
    Description: thesis
    Keywords: 552.1 ; 551.9 ; VBO 000 ; VAD 700 ; VEZ 300 ; TSZ 300 ; Isotopengeologie ; Regionaler Vulkanismus {Geologie} ; Pazifischer Ozean {Geologie} ; Pazifischer Ozean {Geophysik}
    Language: German
    Type: monograph , publishedVersion
    Format: 112 S.
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  • 42
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 551 ; VGA 420 ; Optische Methoden {Mineralogie: Kristallographie}
    Language: German
    Type: monograph , publishedVersion
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  • 43
    Publication Date: 2021-03-29
    Description: Eine der entscheidenden Hauptquellen für Unsicherheiten von Klimaprojektionen ist, wie sensitiv das Klimasystem auf Änderungen der Strahlungsbilanz der Erde reagiert. Angesichts des kontinuierlichen Anstiegs der atmosphärischen Treibhausgaskonzentrationen ist die Einschränkung des Unsicherheitsbereichs dieser Sensitivität von entscheidender Bedeutung. Ein häufig verwendetes Maß zur Beschreibung dieser charakteristischen Kenngröße von Klimamodellen ist die sogenannte Klimasensitivität, definiert als die Gleichgewichtsänderung der simulierten globalen Mitteltemperatur, welche sich aus einer Verdoppelung des atmosphärischen CO2-Gehalts ergibt...
    Description: thesis
    Keywords: 551.6 ; TWC 100 ; TVH 100
    Language: English
    Type: monograph , publishedVersion
    Format: 107 S.
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  • 44
    Publication Date: 2021-03-29
    Description: Diese Arbeit beschäftigt sich mit der chemischen Ozonzerstörung im arktischen und antarktischen stratosphärischen Polarwirbel. Diese wird durch Abbauprodukte von anthropogen emittierten Fluorchlorkohlenwasserstoffen und Halonen, Chlor- und Bromradikale, verursacht. Studien in denen der gemessene und modellierte Ozonabbau verglichen wird zeigen, dass die Prozeße bekannt sind, der quantitative Verlauf allerdings nicht vollständig verstanden ist...
    Description: thesis
    Keywords: 551.5 ; 550
    Language: German
    Type: monograph , publishedVersion
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  • 45
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 551.1 ; 550 ; VKA 150 ; TOO 000 ; Physikalische Petrologie ; Geothermik {Geophysik}
    Language: German
    Type: monograph , publishedVersion
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  • 46
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 622.15 ; 552.5 ; 624.51 ; 550 ; VBP 800 ; TQJ 000 ; Ingenieurgeologie bei der unterirdischen Speicherung und Lagerung ; Geophysikalische Methoden in anderen Wissenschaftsgebieten
    Language: German
    Type: monograph , publishedVersion
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  • 47
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 551.5 ; 550 ; TUA 700 ; TVH 300 ; Verfahren zur Untersuchung der freien Atmosphäre {Meteorologie} ; Lufttemperatur {Meteorologie}
    Language: English
    Type: monograph , publishedVersion
    Format: 153 S.
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  • 48
    Publication Date: 2021-03-29
    Description: With regard to geodesy optimizing procedures for nonlinear adjustment problems are presented. The procedures can be divided into local and global optimization techniques according to the type of the problem. If good initial values are given, the usage of local optimization techniques, (e.g., the Gauß-Newton procedure) is justified. If this is not the case, and the minimizing function has various local minimums, a global strategy must be implemented. Applying global optimization techniques one will not yield the global solution with certainty; only a probabilistic solution will be obtained. Nevertheless, combining local and global strategy and inclusion of all available a priori-information, a global optimizing system can be established that yields practical results for a wide area of problems. With the increase of the capacity of modern computers the efficiency of global optimization algorithms comes along ...
    Description: thesis
    Keywords: 526.9 ; 550 ; UND 000 ; Fehlertheorie {Praktische Geodäsie}
    Language: German
    Type: monograph , publishedVersion
    Format: 85 S.
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  • 49
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 622.15 ; 550 ; Elektrische Verfahren {Geophysik} ; Mitteleuropa {Geophysik}
    Language: German
    Type: monograph , publishedVersion
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  • 50
    Publication Date: 2021-03-29
    Description: Am Ausgangspunkt dieser Arbeit stand die Frage, ob und in welcher Form beim Bau der Autobahnen vor 1933 in Deutschland, Frankreich und Italien die Wahrnehmung von Landschaft' berücksichtigt wurde. Da die Diskussion um die veränderte Wahrnehmung von Landschaft' bei steigender Reisegeschwindigkeit erstmals intensiv im Zusammenhang mit dem Bau der Eisenbahnen im 19. Jahrhundert geführt wurde, leitet ein Rückblick auf diese Zeit die Arbeit ein. Hier konnte die historische Dimension des Untersuchungsthemas verdeutlicht sowie dessen wesentliche Diskussionspunkte aufzeigt werden, die - in modifizierter Form - ein knappes Jahrhundert später bei der Planung und beim Bau der Autobahnen erneut aufgegriffen wurden. Der italienische Futurismus wurde anschließend daraufhin untersucht, ob er neue Darstellungsformen für die veränderte Wahrnehmung von Landschaft' hervorgebracht hat. Das nachfolgende Kapitel diente dazu, die Bedeutung des Themas der Arbeit aufzuzeigen. Eine zusammenstellende Übersicht über den Status des Autobahnbaus und der Autobahnplanungen in Deutschland Frankreich und Italien vor 1933, die bis dato fehlte, wurde hier gegeben. Von zentraler Bedeutung war im Rahmen dieser Arbeit die Analyse der Gestaltungselemente ...
    Description: thesis
    Keywords: 944 ; QEB 000 ; Geographische Umweltwahrnehmung und Raumbewertung
    Language: German
    Type: monograph , publishedVersion
    Format: 307 S.
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  • 51
    Publication Date: 2021-03-29
    Description: Die stärksten Erdbeben treten an Subduktionszonen auf, so z.B. das stärkste instrumentell jemals gemessene Erdbeben vom 22. Mai 1960 mit einer Magnitude von 9,5 Mw in Süd Chile. In dieser Arbeit werden lokal gewonnene seismologische Daten aus dem zentralen Bereich des 1960er-Bebens vorgestellt. Das seismologische Netzwerk umfasste den chilenischen Forearc zwischen Tiefseegraben und den vulkanischen Bogen zwischen 41,5ʿ-43,5ʿS und überdeckte sowohl die Insel Chiloé als auch die Nord-Süd-streichende Liquiñe-Ofqui Störungszone (LOFZ). Zwischen November 2004 und Oktober 2005 konnten 364 lokale Ereignisse registriert werden. Die gewonnen Aufzeichnungen erlauben Aussagen sowohl über das aktuelle Spannungsfeld im Forearc als auch über das lokale Geschwindigkeitsmodell und die Geometrie der subduzierten Benioff-Zone.
    Description: thesis
    Keywords: 551.22 ; 551.136 ; 550 ; TSX 500 ; VAE 700 ; Chile {Geophysik} ; Bau der Erdkruste großer Regionen der Erde {Geologie}
    Language: English
    Type: monograph , publishedVersion
    Format: 134 S.
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  • 52
    Publication Date: 2021-03-29
    Description: Durch den Prozess der Urbanisierung verändert die Menschheit die Erdoberfläche in großem Ausmaß und auf unwiederbringliche Weise. Die optische Fernerkundung ist eine Art der Erdbeobachtung, die das Verständnis dieses dynamischen Prozesses und seiner Auswirkungen erweitern kann. Die vorliegende Arbeit untersucht, inwiefern hyperspektrale Daten Informationen über Versiegelung liefern können, die der integrierten Analyse urbaner Mensch-Umwelt-Beziehungen dienen. Hierzu wird die Verarbeitungskette von Vorverarbeitung der Rohdaten bis zur Erstellung referenzierter Karten zu Landbedeckung und Versiegelung am Beispiel von Hyperspectral Mapper Daten von Berlin ganzheitlich untersucht. Die traditionelle Verarbeitungskette wird mehrmals erweitert bzw. abgewandelt. So wird die radiometrische Vorverarbeitung um die Normalisierung von Helligkeitsgradienten erweitert, welche durch die direktionellen Reflexionseigenschaften urbaner Oberflächen entstehen. Die Klassifikation in fünf spektral komplexe Landnutzungsklassen wird mit Support Vector Maschinen ohne zusätzliche Merkmalsextraktion oder Differenzierung von Subklassen durchgeführt...
    Description: thesis
    Keywords: 550.28 ; 622.159 ; 550 ; TQH 000 ; Aerogeophysik
    Language: English
    Type: monograph , publishedVersion
    Format: 276 S.
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  • 53
    Publication Date: 2021-03-29
    Description: Im Rahmen der Dissertation wurden an Wässern und freien Gasen aus Thermalquellen sowie an weniger als 5 Millionen Jahre alten basischen Vulkaniten des zentralandinen Puna-Hochplateaus (NE-Argentinien) umfangreiche element- und isotopengeochemische Untersuchungen durchgeführt und die Edelgasgehalte und -isotopensignaturen in diesen Medien bestimmt. Damit soll ein Beitrag zum besseren Verständnis der jüngeren Subduktionsgeschichte im Bereich der südlichen Zentralanden geleistet, die Wechselwirkungen zwischen ozeanischer Unter- und kontinentaler Oberplatte sichtbar gemacht und die Edelgassystematik verbessert werden. Wie die Ergebnisse der Untersuchungen an Gasen aus den Thermalquellen der Puna-Region zeigen, ist der Anteil an Mantel-Helium in den Thermalquellen dieser Region mit bis zu 67 % wesentlich höher als in der westlich gelegenen vulkanisch aktiven Westkordillere und den anderen angrenzenden Gebieten. In einigen Quellen konnten sogar Anteile an Mantel-Neon nachgewiesen werden, was aufgrund von Überlagerungen mit Neon atmosphärischen und krustalen Ursprungs weltweit bisher nur vereinzelt gelungen ist. Für kontinentale Bereiche mit großer Krustendicke ist ein solch starker Mantelgasfluss äußerst ungewöhnlich und bedeutet, dass Mantelschmelzen bis in die Kruste aufgedrungen sind und tief reichende Wegsamkeiten existieren, so dass die Mantelgase aufsteigen können, ohne stark krustal beeinflusst zu werden. Dass im Bereich der Puna rezent Mantelmaterial in die Kruste aufsteigt, zu diesem Ergebnis kommen auch aktuelle seismologische Untersuchungen...
    Description: thesis
    Keywords: 551.1 ; VAE 200 ; TOE 000 ; VAE 200 ; TOE 000 ; Geodynamik der Lithosphäre {Geologie} ; Physikalisches Verhalten der Erde {Geophysik}
    Language: German
    Type: monograph , publishedVersion
    Format: 228 S.
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  • 54
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 551 ; 550 ; TOD 400 ; TOE 000 ; TSB 000 ; Erdmantel {Geophysik} ; Physikalisches Verhalten der Erde {Geophysik} ; Mitteleuropa {Geophysik}
    Language: English
    Type: monograph , publishedVersion
    Format: 147 S.
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  • 55
    facet.materialart.
    Unknown
    Univ. Potsdam
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 551.22 ; 550 ; TOH 200 ; Seismische Vorhersagen {Geophysik}
    Language: English
    Type: monograph , publishedVersion
    Format: 230 S.
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  • 56
    Publication Date: 2021-03-29
    Description: Die P- und S-Wellen-Geschwindigkeitsstruktur der D Schicht unter dem südwestlichen Pazifik wurde mittels kurzperiodischer Daten von 12 Tiefbeben in der Tonga-Fiji-Region untersucht, die vom J-Array und Hi-net-Array in Japan registriert wurden. Es wurde für Punktstreuer und ebene Schichten migriert, um schwache Signale zu extrahieren, die an relativ kleinräumigen Heterogenitäten des unteren Mantels entstehen. Um eine höhere Auflösung zu erzielen, wurde die Double Array-Methode (DAM) verwendet, die Empfängerarray und Quellarray gleichzeitig nutzt. Hierbei ist auch das Phase-Weighted Stack-Verfahren angewendet worden, um inkohärentes Rauschen zu reduzieren und somit schwache kohärente Signale aus dem unteren Mantel aufzulösen. Das Ergebnis der Ebenen-Schichten-Methode (RWB) zeigt, dass sich in der D-Schicht negative Geschwindigkeitsdiskontinuitäten mit P-Wellen Geschwindigkeitskontrasten von höchstens 1 % in den Tiefen von 2520 km und 2650 km befinden. Zusätzlich befindet sich eine positive Geschwindigkeitsdiskontinuitäten in der Tiefe von 2800 km. Bei den S Wellen treten Geschwindigkeitsdiskontinuitäten in einer Tiefe von etwa 2550 km und 2850 km auf. Die scheinbare Verschiebung (50 km) der S-Wellen-Geschwindigkeitsdiskontinuität in der Tiefe von 2850 km deutet darauf hin, daß die S-Wellen-Geschwindigkeitsreduktion im unteren Mantel 2-3 mal stärker ist als die P- Wellen-Geschwindigkeitsreduktion...
    Description: thesis
    Keywords: 551.22 ; 550
    Language: English
    Type: monograph , publishedVersion
    Format: 145 S.
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  • 57
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 910 ; QGJ 120 ; Teilfragen zu Indien {Geographie}
    Language: German
    Type: monograph , publishedVersion
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  • 58
    Publication Date: 2021-03-29
    Description: Collisions of black holes and neutron stars, named mixed binaries in the following, are interesting because of at least two reasons. Firstly, it is expected that they emit a large amount of energy as gravitational waves, which could be measured by new detectors. The form of those waves is expected to carry information about the internal structure of such systems. Secondly, collisions of such objects are the prime suspects of short gamma ray bursts. The exact mechanism for the energy emission is unknown so far...
    Description: thesis
    Keywords: 523 ; TEG 400 ; Endstadien von Sternen {Astronomie: Kosmogonie}
    Language: English
    Type: monograph , publishedVersion
    Format: 205 S.
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  • 59
    Publication Date: 2021-03-29
    Description: The search for extrasolar planets is a relatively new field in astronomical and astrophysical sciences that was boosted by the first discovery of the exoplanet 51 Peg b in 1995 by radial velocity measurements. The short orbital period of 4.2 days determined for this giant exoplanet encouraged the accelerated development of another search method due to the high probability that such a Hot Jupiter planet would cross its host star in the line of sight yielding a photometrically detectable signal during this crossing. This transit method (also known as the occultation or eclipse method) measures such a darkening signal as an evidence for an orbiting planet allowing the determination of the radius of the planet. Combined with the information obtained with radial velocity measurements the mass and the density of the planet can be calculated. This unique opportunity to study detailed physical properties of exoplanets is advantageous compared to planets proven only by other search methods. In this thesis the establishing of the new ground-based transit survey Berlin Exoplanet Search Telescope (BEST) is described. This system consists of a 20cm Schmidt telescope and a CCD camera covering a field of view (FOV) of 3.1ʿ x 3.1ʿ. The set-up and the successful implementation of the BEST system are described in this work. Furthermore the developed strategies for the photometric observations, the calibration and analysis of the data, follow-up observations and their optimization are commented. During the 2-year observational campaign (2001-2003) from the Thüringer Landessternwarte (TLS) Tautenburg, Germany, three target fields were observed for 90 nights ...
    Description: thesis
    Keywords: 523 ; THX 100 ; Detektionsmethoden {Astronomie: Extrasolare Planetensysteme}
    Language: English
    Type: monograph , publishedVersion
    Format: 269 S.
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  • 60
    facet.materialart.
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    Univ. Potsdam
    Publication Date: 2021-03-29
    Description: Strong damped Lyman alpha absorption (DLA) lines seen spectra of distant quasar are believed to arise when the sight line to the quasar goes trough the disc of a galaxy or a proto galaxy. Most of the neutral matter in the universe is contained in these clouds of neutral hydrogen that cause the absorption lines. Hence these DLAs are reservoirs for the formation of stars and galaxies throughout the universe. Despite intensive efforts over more than two decades only few galaxies responsible for the DLAs have been found. The problem is that the galaxies that harbour the neutral clouds are not necessarily bright, and selecting galaxies based on absorption lines could well select different types of galaxies than found in large surveys. If we are to understand how galaxies form out of neutral gas clouds it is essential to locate the galaxies in which DLAs reside ...
    Description: thesis
    Keywords: 523 ; TIE 900 ; TIE 400 ; Sonstige Sternensysteme {Astronomie} ; Spektren und Leuchtkraft von Sternsystemen {Astronomie}
    Language: English
    Type: monograph , publishedVersion
    Format: 187 S.
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  • 61
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    Univ. Potsdam
    Publication Date: 2021-03-29
    Description: We investigate the rotational and thermal properties of star-forming molecular clouds using hydrodynamic simulations. Stars form from molecular cloud cores by gravoturbulent fragmentation. Understanding the angular momentum and the thermal evolution of cloud cores thus plays a fundamental role in completing the theoretical picture of star formation. This is true not only for current star formation as observed in regions like the Orion nebula or the ?-Ophiuchi molecular cloud but also for the formation of stars of the first or second generation in the universe...
    Description: thesis
    Keywords: 523 ; TEG 000 ; Kosmogonie {Astronomie}
    Language: English
    Type: monograph , publishedVersion
    Format: 149 S.
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  • 62
    Publication Date: 2021-03-29
    Description: Optical counterparts of X-ray selected sources to a large part consist of active galactic nuclei (AGN). A large proportion of these counterparts turns out to be optically variable, and because the timescales and manner of this variability can give important clues regarding the physical nature and structure of the counterparts, searching for variable AGN is a worthwhile undertaking. In order to perform such an optical variability survey, a subset of 167 X-ray sources in an area around the NEP was selected in this work from the X-ray catalogues derived from the ROSAT all-sky survey (RASS). Contemporaneous optical observations were available from a collaboration with the Karl-Schwarzschildt observatory (KSO) Tautenburg. A total of 89 plates were analyzed, covering an area of 35 degrees square around the NEP and spanning a timebase of 30 month ...
    Description: thesis
    Keywords: 523 ; TBK 000 ; TC 200 ; Hochenergieastronomie ; Astronomische Beobachtungen vom Weltraum aus
    Language: English
    Type: monograph , publishedVersion
    Format: 283 S.
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  • 63
    facet.materialart.
    Unknown
    Univ. Potsdam
    Publication Date: 2021-03-29
    Description: Der Aralsee ist ein intrakontinental gelegenes endorheisches Gewässer fernab von ozeanischen Einflüssen, welches ein exzellentes sedimentäres Archiv für hochauflösende Paläoklimastudien in Zentralasien darstellt. In der vorliegenden Studie wurden umfangreiche palynologische, mikrofazielle und geochemische Analysen anhand von mehreren Bohrkernen aus der Chernyshov-Bucht im NW des heutigen Großen Aralsees durchgeführt. Die vollständigste der erbohrten Sequenzen weist dabei eine Länge von 11 m auf und beinhaltet näherungsweise die letzten 2000 Jahre des Holozän. 〈br〉〈br〉 Die hochauflösenden palynologischen Analysen der Studie, welche sowohl die Untersuchung von Dinoflagellatenzysten als auch Pollen beinhaltet, zeugen von einschneidenden Umweltveränderungen im Aralsee und seinem Einzugsgebiet. Die Untersuchung von Diversität und räumlicher Verbreitung der fossilen Dinoflagellatenzysten vermittelt dabei ein genaues Bild von den Salinitäts- und Seespiegeländerungen der letzten 2000 Jahre. Aufgrund der weitgehenden Abhängigkeit der hydrologischen Verhältnisse des Aralsees von der Wasserführung seinen tributären Flüsse, hängt sein Seespiegel unmittelbar von den Schmelzwasserzuflüssen im Frühjahr ab. Da der Schmelzwasserzufluss seinerseits mit den Temperaturveränderungen im Tien Shan und Pamir während der Schneeschmelze in Verbindung steht, spiegeln die Paläo-Salinität und der Paläo-Seespiegel des Aralsees folglich die Temperaturveränderungen im hochgelegenen Einzugsgebiet des Aralsees wider...
    Description: thesis
    Keywords: 551 ; VKB 380 ; VDI 220 ; TWC 500 ; Sedimente bestimmter Regionen ; Holozän ; Klimaschwankungen und Klimaänderungen im Quartär
    Language: English
    Type: monograph , publishedVersion
    Format: 138 S.
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  • 64
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 549 ; VGF 200 ; VHB 830 ; Phasengleichgewichte und Umbildungen {Mineralogie} ; Gruppensilikate {Mineralogie}
    Language: German
    Type: monograph , publishedVersion
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  • 65
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 551.9 ; VOBC 700 ; VBQ 400 ; Transportvorgänge in Böden ; Grundwassergefährdung {Hydrogeologie}
    Language: German
    Type: monograph , publishedVersion
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  • 66
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 551.9 ; VJF 000 ; VJC 400 ; VEB 217 ; Umweltgeochemie insgesamt ; Fluid-Gestein-Wechselwirkungen {Geochemie} ; Sachsen {Geologie}
    Language: German
    Type: monograph , publishedVersion
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  • 67
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    Univ. Berlin
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 551 ; VAE 850 ; VAE 400 ; VDE 000 ; VEO 170 ; Festländische Lineamente {Geologie} ; Tektogenese {Geologie} ; Proterozoikum ; Sudan {Geologie}
    Language: English
    Type: monograph , publishedVersion
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  • 68
    Publication Date: 2021-03-29
    Description: The separation of natural and anthropogenically caused climatic changes is an important task of contemporary climate research. For this purpose, a detailed knowledge of the natural variability of the climate during warm stages is a necessary prerequisite. Beside model simulations and historical documents, this knowledge is mostly derived from analyses of so-called climatic proxy data like tree rings or sediment as well as ice cores. In order to be able to appropriately interpret such sources of palaeoclimatic information, suitable approaches of statistical modelling as well as methods of time series analysis are necessary, which are applicable to short, noisy, and non-stationary uni- and multivariate data sets. Correlations between different climatic proxy data within one or more climatological archives contain significant information about the climatic change on longer time scales. Based on an appropriate statistical decomposition of such multivariate time series, one may estimate dimensions in terms of the number of significant, linear independent components of the considered data set. In the presented work, a corresponding approach is introduced, critically discussed, and extended with respect to the analysis of palaeoclimatic time series. Temporal variations of the resulting measures allow to derive information about climatic changes ...
    Description: thesis
    Keywords: 551.6 ; VBE 000 ; TWC 100 ; Modellierung von Prozessen in der Geosphäre ; Instr. Ergebn. zu Klimaänderungen und Klimaschwankungen
    Language: English
    Type: monograph , publishedVersion
    Format: 169 S.
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  • 69
    Publication Date: 2021-03-29
    Description: The Andean orogen is the most outstanding example of mountain building caused by the subduction of oceanic below continental lithosphere. The Andes formed by the subduction of the Nazca and Antarctic oceanic plates under the South American continent over at least ~200 million years. Tectonic and climatic conditions vary markedly along this north-southoriented plate boundary, which thus represents an ideal natural laboratory to study tectonic and climatic segmentation processes and their possible feedbacks. Most of the seismic energy on Earth is released by earthquakes in subduction zones, like the giant 1960, Mw 9.5 event in south-central Chile.
    Description: thesis
    Keywords: 551.22 ; 551 ; 550 ; TSX 500 ; VEX 100 ; VEX 500 ; VAE 500 ; TOH 800 ; Chile {Geophysik} ; Anden {Geologie} ; Chile {Geologie} ; Geotektonische Entwicklung der Erdkruste {Tektonik} ; Paläoerdbeben {Geophysik}
    Language: English
    Type: monograph , publishedVersion
    Format: 120 S.
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  • 70
    Publication Date: 2021-03-29
    Description: To understand processes and dynamics linked to the volumetric water content of soils thorough knowledge of the water distribution inside soils is required. The applicability of the georadar technique for small scale soil heterogeneity mapping and monitoring is investigated using four different methods. Since the uppermost meter of the soil lacks a sufficient amount of spacious reflectors no standard georadar methods can supply adequate coverage of the investigated area under field conditions. Therefore four methods were evaluated to present an assortment of the most promising methods for different case specific problems. Owing to the averaging nature of the georadar technique the introduced methods needed to be adapted to small scale investigations. Based on numerical simulations and concise measurements new processing procedures are applied to achieve the required spatial resolution of less than 0.3 m. All four methods were successfully applied during realistic field measurement conditions. The transmission method is applied to a soil column experiment filled with undisturbed natural soil. In the course of an irrigation experiment the infiltration of the water front as well as the water dynamics afterwards were reproduced. The application of georadar transmission tomography provided spatial allocatable water content distributions over the time of the water seepage with spatial accuracies of approximately 0.1 m and a temporal resolution of approximately 30 min...
    Description: thesis
    Keywords: 551.48 ; 550.28 ; 550 ; TQD 800 ; Georadar {Geophysik}
    Language: English
    Type: monograph , publishedVersion
    Format: 146 S.
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  • 71
    Publication Date: 2021-03-29
    Description: Im Rahmen verschiedener Drittelmittelprojekte waren vom Autor Wechselstrommessungen bei z.T. sehr kleinen Signal- zu Rauschverhältnissen durchzuführen. In den ariden Messgebieten (Ägypten, Sudan) waren hierfür die schlechten Ankopplungsbedingungen verantwortlich, in den dicht besiedelten Gebieten (Stadtgebiet Berlin) die hohen Störspannungspegel. Trotz konsequenter Anwendung von Filter- und Stapelungstechniken, blieb die Datenqualität bisweilen unakzeptabel niedrig. Inspiriert durch multivariate Zeitreihenanalysentechniken der Audiomagnetotellurik wurde vom Autor eine geoelektrische Referenztechnik mathematisch formuliert und mit Hilfe von speziell hierfür gefertigten mehrkanaligen Geoelektrikapparaturen erfolgreich eingesetzt. Anhand von Fallbeispielen wurde demonstriert, dass die Anwendung der geoelektrischen Referenztechnik den statistischen Messfehler sowohl im Gelände als auch im Labor um bis zu 2 Größenordnungen verringern kann. Anders als Stapelungstechniken vermindert die Referenztechnik den Messfortschritt jedoch nicht. Ein ungünstig gewählter Referenzstationsstandort kann zu systematisch verfälschten Messwerten führen. Anhand von Modellrechnungen wurde untersucht welche Anordnungen vorteilhaft sind...
    Description: thesis
    Keywords: 537 ; 550 ; TQD 000
    Language: German
    Type: monograph , publishedVersion
    Format: 325 S.
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  • 72
    facet.materialart.
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    Univ. Berlin
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 550.28 ; 550 ; VBH 000 ; VBH 000 ; Fernerkundung
    Language: English
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  • 73
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 622.15 ; 551.1 ; 550 ; TQG 000 ; TOO 000 ; TOD 410 ; TSV 000 ; TSZ 300 ; TQG 000 ; TOO 000 ; TOD 410 ; TSV 000 ; TSZ 300 ; Geophysikalische Bohrlochmessungen ; Geothermik {Geophysik} ; Oberer Erdmantel {Geophysik} ; Nordamerika {Geophysik} ; Pazifischer Ozean {Geophysik}
    Language: German
    Type: monograph , publishedVersion
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  • 74
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 551.701 ; 549 ; VBN 200 ; VHC 200 ; VBN 200 ; VHC 200 ; Radiometrische Altersbestimmung ; Schwerminerale
    Language: English
    Type: monograph , publishedVersion
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  • 75
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 551.22 ; 550
    Language: English
    Type: monograph , publishedVersion
    Format: 188 S.
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  • 76
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 551 ; VAE 840 ; VEO 170 ; Rifts {Geologie} ; Sudan {Geologie}
    Language: German
    Type: monograph , publishedVersion
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  • 77
    Publication Date: 2021-03-29
    Description: Zu einem aktuellen Thema der Geodäsie werden in Form geeigneter Berechnungsverfahren im Spektralbereich wie auch im Zeitbereich Auswertestrategien zur Bestimmung globaler Erdschwerefeldmodelle anhand von Satellitenbeobachtungsdaten diskutiert. Die praktische Aufgabenstellung zur Bewältigung solcher hochgenauer, automatisierter Messtechniken erfordert ein allgemeines Lösungskonzept mittels dem irregulär verteilte, heterogene Messdaten über ein theoretisch einwandfreies Verfahren miteinander verknüpft werden können. Zur Bildung der Normalgleichungssysteme im Sinne einer Ausgleichung mit voller Korrelation müssen dazu die Beobachtungspositionen anhand der Kugelfunktionen integriert werden. Durch die Zerlegung der Kugelfunktionen in deren spektrale Basisfunktionen lässt sich der notwendige Arbeitsaufwand in zwei grundlegende Arbeitsschritte aufteilen, einmal in Abhängigkeit von der Anzahl der Daten und einmal Abhängig von der Grösse des Rechenmodelles. Die Integration der Daten kann daher im ersten Schritt äusserst effizient vollzogen werden, während die daran anschliessende Berechnung der Normalgleichungen und deren Inversion in Abhängigkeit von der jeweiligen Auflösung als konstant zu betrachten ist...
    Description: thesis
    Keywords: 526.7 ; 550.28 ; 622.15 ; 550 ; TQA 000 ; Gravimetrische Verfahren {Geophysik}
    Language: German
    Type: monograph , publishedVersion
    Format: 123 S.
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  • 78
    facet.materialart.
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    Univ. Potsdam
    Publication Date: 2021-03-29
    Description: Various types of uncertainty plague climate change simulation, which is, in turn, a crucialelement of Earth System modelling. This fact was recognized for example in the Third Assessment Report (TAR) of the Intergovernmental Panel on Climate Change (IPCC, Houghton et al. (2001)), where the authors indicate that for the period between 1990 and 2100 an increase of the global mean temperature around 1.4-5.8°C is to be expected (Houghton et al. 2001). The width of this span as well as the fact that the authors did not give a number concerning the most probable value or a probability distribution shows clearly the large uncertainty. This uncertainty does not only arise due to the different scenarios of future development concerning greenhouse gas emissions for example, but follows to large degree from the wide range of results from different models as well. The chain of these uncertainties of imponderables in the analysis of the Earth System (Schellnhuber and Wenzel 1998), which includes the climate system as well as the anthroposphere, reaches from uncertainties about the existence of critical thresholds, to ignorance of the exact state of today's climate, and ultimately to a lack of knowledge concerning climate-relevant processes, some of which are visible as uncertainties in climate models. Many attempts have been made to reduce these uncertainties by gaining a conceptual understanding of processes, e.g. of El Ni~no / Southern Oscillation (ENSO) (Jin 1997, e.g.) or of the Atlantic overturning (Stommel 1961; Rahmstorf 1996, e.g.), by developing methods to identify critical thresholds in the climate system (Alley et al. 2003; Rial et al. 2004, e.g.), or by implementing an increasing number of processes in a model, resulting in high resolution general circulation models (GCMs), e.g. ECHAM5/MPI-OM (Jungclaus et al. 2006) or HadCM3 (Gordon et al. 2000) and many more. Nevertheless, the much larger part of uncertainties is inevitable in the process of modelling as well as in our understanding of the Earth System. In this thesis we will structure this conglomeration of uncertainties climate research is confronted with. We will address several types of uncertainty and apply methods of dynamical systems theory on a trendsetting field of climate research, i.e. the Indian monsoon ...
    Description: thesis
    Keywords: 551.6 ; TWB 000 ; Statistische Klimatologie und Klimatologische Modelle
    Language: English
    Type: monograph , publishedVersion
    Format: 131 S.
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  • 79
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 522 ; TCE 320 ; Photometer, Polarimeter, spektroskopische Instrumente {Astronomische Instrumente}
    Language: German
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  • 80
    Publication Date: 2021-03-29
    Description: thesis
    Keywords: 910 ; QBD 700 ; QER 800 ; QBD 700 ; QER 800 ; Geoinformationssysteme {Geographie} ; Verkehrsgeographie {Wirtschaftsgeographie}
    Language: English
    Type: monograph , publishedVersion
    Format: 131 S.
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