ALBERT

Description: The accretion of matter onto a massive black hole is believed to feed the relativistic plasma jets found in many active galactic nuclei (AGN). Although some AGN accelerate particles to energies exceeding 10(12) electron volts and are bright sources of very-high-energy (VHE) gamma-ray emission, it is not yet known where the VHE emission originates. Here we report on radio and VHE observations of the radio galaxy Messier 87, revealing a period of extremely strong VHE gamma-ray flares accompanied by a strong increase of the radio flux from its nucleus. These results imply that charged particles are accelerated to very high energies in the immediate vicinity of the black hole.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉VERITAS Collaboration -- VLBA 43 GHz M87 Monitoring Team -- H.E.S.S. Collaboration -- MAGIC Collaboration -- Acciari, V A -- Aliu, E -- Arlen, T -- Bautista, M -- Beilicke, M -- Benbow, W -- Bradbury, S M -- Buckley, J H -- Bugaev, V -- Butt, Y -- Byrum, K -- Cannon, A -- Celik, O -- Cesarini, A -- Chow, Y C -- Ciupik, L -- Cogan, P -- Cui, W -- Dickherber, R -- Fegan, S J -- Finley, J P -- Fortin, P -- Fortson, L -- Furniss, A -- Gall, D -- Gillanders, G H -- Grube, J -- Guenette, R -- Gyuk, G -- Hanna, D -- Holder, J -- Horan, D -- Hui, C M -- Humensky, T B -- Imran, A -- Kaaret, P -- Karlsson, N -- Kieda, D -- Kildea, J -- Konopelko, A -- Krawczynski, H -- Krennrich, F -- Lang, M J -- LeBohec, S -- Maier, G -- McCann, A -- McCutcheon, M -- Millis, J -- Moriarty, P -- Ong, R A -- Otte, A N -- Pandel, D -- Perkins, J S -- Petry, D -- Pohl, M -- Quinn, J -- Ragan, K -- Reyes, L C -- Reynolds, P T -- Roache, E -- Rose, H J -- Schroedter, M -- Sembroski, G H -- Smith, A W -- Swordy, S P -- Theiling, M -- Toner, J A -- Varlotta, A -- Vincent, S -- Wakely, S P -- Ward, J E -- Weekes, T C -- Weinstein, A -- Williams, D A -- Wissel, S -- Wood, M -- Walker, R C -- Davies, F -- Hardee, P E -- Junor, W -- Ly, C -- Aharonian, F -- Akhperjanian, A G -- Anton, G -- Barres de Almeida, U -- Bazer-Bachi, A R -- Becherini, Y -- Behera, B -- Bernlohr, K -- Bochow, A -- Boisson, C -- Bolmont, J -- Borrel, V -- Brucker, J -- Brun, F -- Brun, P -- Buhler, R -- Bulik, T -- Busching, I -- Boutelier, T -- Chadwick, P M -- Charbonnier, A -- Chaves, R C G -- Cheesebrough, A -- Chounet, L-M -- Clapson, A C -- Coignet, G -- Dalton, M -- Daniel, M K -- Davids, I D -- Degrange, B -- Deil, C -- Dickinson, H J -- Djannati-Atai, A -- Domainko, W -- Drury, L O'C -- Dubois, F -- Dubus, G -- Dyks, J -- Dyrda, M -- Egberts, K -- Emmanoulopoulos, D -- Espigat, P -- Farnier, C -- Feinstein, F -- Fiasson, A -- Forster, A -- Fontaine, G -- Fussling, M -- Gabici, S -- Gallant, Y A -- Gerard, L -- Gerbig, D -- Giebels, B -- Glicenstein, J F -- Gluck, B -- Goret, P -- Gohring, D -- Hauser, D -- Hauser, M -- Heinz, S -- Heinzelmann, G -- Henri, G -- Hermann, G -- Hinton, J A -- Hoffmann, A -- Hofmann, W -- Holleran, M -- Hoppe, S -- Horns, D -- Jacholkowska, A -- de Jager, O C -- Jahn, C -- Jung, I -- Katarzynski, K -- Katz, U -- Kaufmann, S -- Kendziorra, E -- Kerschhaggl, M -- Khangulyan, D -- Khelifi, B -- Keogh, D -- Kluzniak, W -- Kneiske, T -- Komin, Nu -- Kosack, K -- Lamanna, G -- Lenain, J-P -- Lohse, T -- Marandon, V -- Martin, J M -- Martineau-Huynh, O -- Marcowith, A -- Maurin, D -- McComb, T J L -- Medina, M C -- Moderski, R -- Moulin, E -- Naumann-Godo, M -- de Naurois, M -- Nedbal, D -- Nekrassov, D -- Nicholas, B -- Niemiec, J -- Nolan, S J -- Ohm, S -- Olive, J-F -- de Ona Wilhelmi, E -- Orford, K J -- Ostrowski, M -- Panter, M -- Paz Arribas, M -- Pedaletti, G -- Pelletier, G -- Petrucci, P-O -- Pita, S -- Puhlhofer, G -- Punch, M -- Quirrenbach, A -- Raubenheimer, B C -- Raue, M -- Rayner, S M -- Renaud, M -- Rieger, F -- Ripken, J -- Rob, L -- Rosier-Lees, S -- Rowell, G -- Rudak, B -- Rulten, C B -- Ruppel, J -- Sahakian, V -- Santangelo, A -- Schlickeiser, R -- Schock, F M -- Schroder, R -- Schwanke, U -- Schwarzburg, S -- Schwemmer, S -- Shalchi, A -- Sikora, M -- Skilton, J L -- Sol, H -- Spangler, D -- Stawarz, L -- Steenkamp, R -- Stegmann, C -- Stinzing, F -- Superina, G -- Szostek, A -- Tam, P H -- Tavernet, J-P -- Terrier, R -- Tibolla, O -- Tluczykont, M -- van Eldik, C -- Vasileiadis, G -- Venter, C -- Venter, L -- Vialle, J P -- Vincent, P -- Vivier, M -- Volk, H J -- Volpe, F -- Wagner, S J -- Ward, M -- Zdziarski, A A -- Zech, A -- Anderhub, H -- Antonelli, L A -- Antoranz, P -- Backes, M -- Baixeras, C -- Balestra, S -- Barrio, J A -- Bastieri, D -- Becerra Gonzalez, J -- Becker, J K -- Bednarek, W -- Berger, K -- Bernardini, E -- Biland, A -- Bock, R K -- Bonnoli, G -- Bordas, P -- Borla Tridon, D -- Bosch-Ramon, V -- Bose, D -- Braun, I -- Bretz, T -- Britvitch, I -- Camara, M -- Carmona, E -- Commichau, S -- Contreras, J L -- Cortina, J -- Costado, M T -- Covino, S -- Curtef, V -- Dazzi, F -- De Angelis, A -- De Cea del Pozo, E -- Delgado Mendez, C -- De los Reyes, R -- De Lotto, B -- De Maria, M -- De Sabata, F -- Dominguez, A -- Dorner, D -- Doro, M -- Elsaesser, D -- Errando, M -- Ferenc, D -- Fernandez, E -- Firpo, R -- Fonseca, M V -- Font, L -- Galante, N -- Garcia Lopez, R J -- Garczarczyk, M -- Gaug, M -- Goebel, F -- Hadasch, D -- Hayashida, M -- Herrero, A -- Hildebrand, D -- Hohne-Monch, D -- Hose, J -- Hsu, C C -- Jogler, T -- Kranich, D -- La Barbera, A -- Laille, A -- Leonardo, E -- Lindfors, E -- Lombardi, S -- Longo, F -- Lopez, M -- Lorenz, E -- Majumdar, P -- Maneva, G -- Mankuzhiyil, N -- Mannheim, K -- Maraschi, L -- Mariotti, M -- Martinez, M -- Mazin, D -- Meucci, M -- Miranda, J M -- Mirzoyan, R -- Miyamoto, H -- Moldon, J -- Moles, M -- Moralejo, A -- Nieto, D -- Nilsson, K -- Ninkovic, J -- Oya, I -- Paoletti, R -- Paredes, J M -- Pasanen, M -- Pascoli, D -- Pauss, F -- Pegna, R G -- Perez-Torres, M A -- Persic, M -- Peruzzo, L -- Prada, F -- Prandini, E -- Puchades, N -- Reichardt, I -- Rhode, W -- Ribo, M -- Rico, J -- Rissi, M -- Robert, A -- Rugamer, S -- Saggion, A -- Saito, T Y -- Salvati, M -- Sanchez-Conde, M -- Satalecka, K -- Scalzotto, V -- Scapin, V -- Schweizer, T -- Shayduk, M -- Shore, S N -- Sidro, N -- Sierpowska-Bartosik, A -- Sillanpaa, A -- Sitarek, J -- Sobczynska, D -- Spanier, F -- Stamerra, A -- Stark, L S -- Takalo, L -- Tavecchio, F -- Temnikov, P -- Tescaro, D -- Teshima, M -- Torres, D F -- Turini, N -- Vankov, H -- Wagner, R M -- Zabalza, V -- Zandanel, F -- Zanin, R -- Zapatero, J -- New York, N.Y. -- Science. 2009 Jul 24;325(5939):444-8. doi: 10.1126/science.1175406. Epub 2009 Jul 2.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Fred Lawrence Whipple Observatory, Harvard-Smithsonian Center for Astrophysics, Amado, AZ 85645, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/19574351" target="_blank"〉PubMed〈/a〉

Description: X-ray binaries are composed of a normal star in orbit around a neutron star or stellar-mass black hole. Radio and x-ray observations have led to the presumption that some x-ray binaries called microquasars behave as scaled-down active galactic nuclei. Microquasars have resolved radio emission that is thought to arise from a relativistic outflow akin to active galactic nuclei jets, in which particles can be accelerated to large energies. Very high energy gamma-rays produced by the interactions of these particles have been observed from several active galactic nuclei. Using the High Energy Stereoscopic System, we find evidence for gamma-ray emission of 〉100 gigaelectron volts from a candidate microquasar, LS 5039, showing that particles are also accelerated to very high energies in these systems.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Aharonian, F -- Akhperjanian, A G -- Aye, K-M -- Bazer-Bachi, A R -- Beilicke, M -- Benbow, W -- Berge, D -- Berghaus, P -- Bernlohr, K -- Boisson, C -- Bolz, O -- Borrel, V -- Braun, I -- Breitling, F -- Brown, A M -- Bussons Gordo, J -- Chadwick, P M -- Chounet, L-M -- Cornils, R -- Costamante, L -- Degrange, B -- Dickinson, H J -- Djannati-Atai, A -- Drury, L O'c -- Dubus, G -- Emmanoulopoulos, D -- Espigat, P -- Feinstein, F -- Fleury, P -- Fontaine, G -- Fuchs, Y -- Funk, S -- Gallant, Y A -- Giebels, B -- Gillessen, S -- Glicenstein, J F -- Goret, P -- Hadjichristidis, C -- Hauser, M -- Heinzelmann, G -- Henri, G -- Hermann, G -- Hinton, J A -- Hofmann, W -- Holleran, M -- Horns, D -- Jacholkowska, A -- de Jager, O C -- Khelifi, B -- Komin, Nu -- Konopelko, A -- Latham, I J -- Le Gallou, R -- Lemiere, A -- Lemoine-Goumard, M -- Leroy, N -- Lohse, T -- Marcowith, A -- Martin, J-M -- Martineau-Huynh, O -- Masterson, C -- McComb, T J L -- de Naurois, M -- Nolan, S J -- Noutsos, A -- Orford, K J -- Osborne, J L -- Ouchrif, M -- Panter, M -- Pelletier, G -- Pita, S -- Puhlhofer, G -- Punch, M -- Raubenheimer, B C -- Raue, M -- Raux, J -- Rayner, S M -- Reimer, A -- Reimer, O -- Ripken, J -- Rob, L -- Rolland, L -- Rowell, G -- Sahakian, V -- Sauge, L -- Schlenker, S -- Schlickeiser, R -- Schuster, C -- Schwanke, U -- Siewert, M -- Sol, H -- Spangler, D -- Steenkamp, R -- Stegmann, C -- Tavernet, J-P -- Terrier, R -- Theoret, C G -- Tluczykont, M -- Vasileiadis, G -- Venter, C -- Vincent, P -- Volk, H J -- Wagner, S J -- New York, N.Y. -- Science. 2005 Jul 29;309(5735):746-9. Epub 2005 Jul 7.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Max-Planck-Institut fur Kernphysik, Post Office Box 103980, D-69029 Heidelberg, Germany.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/16002580" target="_blank"〉PubMed〈/a〉

Description: Very high energy gamma-rays probe the long-standing mystery of the origin of cosmic rays. Produced in the interactions of accelerated particles in astrophysical objects, they can be used to image cosmic particle accelerators. A first sensitive survey of the inner part of the Milky Way with the High Energy Stereoscopic System (HESS) reveals a population of eight previously unknown firmly detected sources of very high energy gamma-rays. At least two have no known radio or x-ray counterpart and may be representative of a new class of "dark" nucleonic cosmic ray sources.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Aharonian, F -- Akhperjanian, A G -- Aye, K-M -- Bazer-Bachi, A R -- Beilicke, M -- Benbow, W -- Berge, D -- Berghaus, P -- Bernlohr, K -- Boisson, C -- Bolz, O -- Borgmeier, C -- Braun, I -- Breitling, F -- Brown, A M -- Gordo, J Bussons -- Chadwick, P M -- Chounet, L-M -- Cornils, R -- Costamante, L -- Degrange, B -- Djannati-Atai, A -- Drury, L O'C -- Dubus, G -- Ergin, T -- Espigat, P -- Feinstein, F -- Fleury, P -- Fontaine, G -- Funk, S -- Gallant, Y A -- Giebels, B -- Gillessen, S -- Goret, P -- Hadjichristidis, C -- Hauser, M -- Heinzelmann, G -- Henri, G -- Hermann, G -- Hinton, J A -- Hofmann, W -- Holleran, M -- Horns, D -- de Jager, O C -- Jung, I -- Khelifi, B -- Komin, Nu -- Konopelko, A -- Latham, I J -- Le Gallou, R -- Lemiere, A -- Lemoine, M -- Leroy, N -- Lohse, T -- Marcowith, A -- Masterson, C -- McComb, T J L -- de Naurois, M -- Nolan, S J -- Noutsos, A -- Orford, K J -- Osborne, J L -- Ouchrif, M -- Panter, M -- Pelletier, G -- Pita, S -- Puhlhofer, G -- Punch, M -- Raubenheimer, B C -- Raue, M -- Raux, J -- Rayner, S M -- Redondo, I -- Reimer, A -- Reimer, O -- Ripken, J -- Rob, L -- Rolland, L -- Rowell, G -- Sahakian, V -- Sauge, L -- Schlenker, S -- Schlickeiser, R -- Schuster, C -- Schwanke, U -- Siewert, M -- Sol, H -- Steenkamp, R -- Stegmann, C -- Tavernet, J-P -- Terrier, R -- Theoret, C G -- Tluczykont, M -- van der Walt, D J -- Vasileiadis, G -- Venter, C -- Vincent, P -- Visser, B -- Volk, H J -- Wagner, S J -- New York, N.Y. -- Science. 2005 Mar 25;307(5717):1938-42.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Max-Planck-Institut fur Kernphysik, Post Office Box 103980, D-69029 Heidelberg, Germany.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/15790849" target="_blank"〉PubMed〈/a〉

Description: The detection of fast variations of the tera-electron volt (TeV) (10(12) eV) gamma-ray flux, on time scales of days, from the nearby radio galaxy M87 is reported. These variations are about 10 times as fast as those observed in any other wave band and imply a very compact emission region with a dimension similar to the Schwarzschild radius of the central black hole. We thus can exclude several other sites and processes of the gamma-ray production. The observations confirm that TeV gamma rays are emitted by extragalactic sources other than blazars, where jets are not relativistically beamed toward the observer.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Aharonian, F -- Akhperjanian, A G -- Bazer-Bachi, A R -- Beilicke, M -- Benbow, W -- Berge, D -- Bernlohr, K -- Boisson, C -- Bolz, O -- Borrel, V -- Braun, I -- Brown, A M -- Buhler, R -- Busching, I -- Carrigan, S -- Chadwick, P M -- Chounet, L-M -- Coignet, G -- Cornils, R -- Costamante, L -- Degrange, B -- Dickinson, H J -- Djannati-Atai, A -- Drury, L O'c -- Dubus, G -- Egberts, K -- Emmanoulopoulos, D -- Espigat, P -- Feinstein, F -- Ferrero, E -- Fiasson, A -- Fontaine, G -- Funk, Seb -- Funk, S -- Fussling, M -- Gallant, Y A -- Giebels, B -- Glicenstein, J F -- Goret, P -- Hadjichristidis, C -- Hauser, D -- Hauser, M -- Heinzelmann, G -- Henri, G -- Hermann, G -- Hinton, J A -- Hoffmann, A -- Hofmann, W -- Holleran, M -- Hoppe, S -- Horns, D -- Jacholkowska, A -- de Jager, O C -- Kendziorra, E -- Kerschhaggl, M -- Khelifi, B -- Komin, Nu -- Konopelko, A -- Kosack, K -- Lamanna, G -- Latham, I J -- Le Gallou, R -- Lemiere, A -- Lemoine-Goumard, M -- Lenain, J-P -- Lohse, T -- Martin, J M -- Martineau-Huynh, O -- Marcowith, A -- Masterson, C -- Maurin, G -- McComb, T J L -- Moulin, E -- de Naurois, M -- Nedbal, D -- Nolan, S J -- Noutsos, A -- Orford, K J -- Osborne, J L -- Ouchrif, M -- Panter, M -- Pelletier, G -- Pita, S -- Puhlhofer, G -- Punch, M -- Ranchon, S -- Raubenheimer, B C -- Raue, M -- Rayner, S M -- Reimer, A -- Ripken, J -- Rob, L -- Rolland, L -- Rosier-Lees, S -- Rowell, G -- Sahakian, V -- Santangelo, A -- Sauge, L -- Schlenker, S -- Schlickeiser, R -- Schroder, R -- Schwanke, U -- Schwarzburg, S -- Schwemmer, S -- Shalchi, A -- Sol, H -- Spangler, D -- Spanier, F -- Steenkamp, R -- Stegmann, C -- Superina, G -- Tam, P H -- Tavernet, J-P -- Terrier, R -- Tluczykont, M -- van Eldik, C -- Vasileiadis, G -- Venter, C -- Vialle, J P -- Vincent, P -- Volk, H J -- Wagner, S J -- Ward, M -- New York, N.Y. -- Science. 2006 Dec 1;314(5804):1424-7. Epub 2006 Oct 26.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Max-Planck-Institut fur Kernphysik, Post Office Box 103980, D 69029 Heidelberg, Germany.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/17068224" target="_blank"〉PubMed〈/a〉

Description: We report the detection of pulsed gamma rays from the Crab pulsar at energies above 100 giga-electron volts (GeV) with the Very Energetic Radiation Imaging Telescope Array System (VERITAS) array of atmospheric Cherenkov telescopes. The detection cannot be explained on the basis of current pulsar models. The photon spectrum of pulsed emission between 100 mega-electron volts and 400 GeV is described by a broken power law that is statistically preferred over a power law with an exponential cutoff. It is unlikely that the observation can be explained by invoking curvature radiation as the origin of the observed gamma rays above 100 GeV. Our findings require that these gamma rays be produced more than 10 stellar radii from the neutron star.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉VERITAS Collaboration -- Aliu, E -- Arlen, T -- Aune, T -- Beilicke, M -- Benbow, W -- Bouvier, A -- Bradbury, S M -- Buckley, J H -- Bugaev, V -- Byrum, K -- Cannon, A -- Cesarini, A -- Christiansen, J L -- Ciupik, L -- Collins-Hughes, E -- Connolly, M P -- Cui, W -- Dickherber, R -- Duke, C -- Errando, M -- Falcone, A -- Finley, J P -- Finnegan, G -- Fortson, L -- Furniss, A -- Galante, N -- Gall, D -- Gibbs, K -- Gillanders, G H -- Godambe, S -- Griffin, S -- Grube, J -- Guenette, R -- Gyuk, G -- Hanna, D -- Holder, J -- Huan, H -- Hughes, G -- Hui, C M -- Humensky, T B -- Imran, A -- Kaaret, P -- Karlsson, N -- Kertzman, M -- Kieda, D -- Krawczynski, H -- Krennrich, F -- Lang, M J -- Lyutikov, M -- Madhavan, A S -- Maier, G -- Majumdar, P -- McArthur, S -- McCann, A -- McCutcheon, M -- Moriarty, P -- Mukherjee, R -- Nunez, P -- Ong, R A -- Orr, M -- Otte, A N -- Park, N -- Perkins, J S -- Pizlo, F -- Pohl, M -- Prokoph, H -- Quinn, J -- Ragan, K -- Reyes, L C -- Reynolds, P T -- Roache, E -- Rose, H J -- Ruppel, J -- Saxon, D B -- Schroedter, M -- Sembroski, G H -- Senturk, G D -- Smith, A W -- Staszak, D -- Tesic, G -- Theiling, M -- Thibadeau, S -- Tsurusaki, K -- Tyler, J -- Varlotta, A -- Vassiliev, V V -- Vincent, S -- Vivier, M -- Wakely, S P -- Ward, J E -- Weekes, T C -- Weinstein, A -- Weisgarber, T -- Williams, D A -- Zitzer, B -- New York, N.Y. -- Science. 2011 Oct 7;334(6052):69-72. doi: 10.1126/science.1208192.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Physics and Astronomy, Barnard College, Columbia University, NY 10027, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/21980105" target="_blank"〉PubMed〈/a〉