@misc{FedericiPohlRuppeletal.2011, author = {Federici, S. and Pohl, Martin and Ruppel, J. and Telezhinsky, Igor O. and Hofmann, Werner and Martinez, M. and Knapp, J.}, title = {Design concepts for the Cherenkov Telescope Array CTA}, series = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, volume = {32}, journal = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1325}, issn = {1866-8372}, doi = {10.25932/publishup-43014}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-430149}, pages = {124}, year = {2011}, abstract = {Ground-based gamma-ray astronomy has had a major breakthrough with the impressive results obtained using systems of imaging atmospheric Cherenkov telescopes. Ground-based gamma-ray astronomy has a huge potential in astrophysics, particle physics and cosmology. CTA is an international initiative to build the next generation instrument, with a factor of 5-10 improvement in sensitivity in the 100 GeV-10 TeV range and the extension to energies well below 100 GeV and above 100 TeV. CTA will consist of two arrays (one in the north, one in the south) for full sky coverage and will be operated as open observatory. The design of CTA is based on currently available technology. This document reports on the status and presents the major design concepts of CTA.}, language = {en} } @article{ActisAgnettaAharonianetal.2011, author = {Actis, M. and Agnetta, G. and Aharonian, Felix A. and Akhperjanian, A. G. and Aleksic, J. and Aliu, E. and Allan, D. and Allekotte, I. and Antico, F. and Antonelli, L. A. and Antoranz, P. and Aravantinos, A. and Arlen, T. and Arnaldi, H. and Artmann, S. and Asano, K. and Asorey, H. G. and Baehr, J. and Bais, A. and Baixeras, C. and Bajtlik, S. and Balis, D. and Bamba, A. and Barbier, C. and Barcelo, M. and Barnacka, Anna and Barnstedt, J{\"u}rgen and de Almeida, U. Barres and Barrio, J. A. and Basso, S. and Bastieri, D. and Bauer, C. and Becerra Gonzalez, J. and Becherini, Yvonne and Bechtol, K. C. and Becker, J. and Beckmann, Volker and Bednarek, W. and Behera, B. and Beilicke, M. and Belluso, M. and Benallou, M. and Benbow, W. and Berdugo, J. and Berger, K. and Bernardino, T. and Bernl{\"o}hr, K. and Biland, A. and Billotta, S. and Bird, T. and Birsin, E. and Bissaldi, E. and Blake, S. and Blanch Bigas, O. and Bobkov, A. A. and Bogacz, L. and Bogdan, M. and Boisson, Catherine and Boix Gargallo, J. and Bolmont, J. and Bonanno, G. and Bonardi, A. and Bonev, T. and Borkowski, Janett and Botner, O. and Bottani, A. and Bourgeat, M. and Boutonnet, C. and Bouvier, A. and Brau-Nogue, S. and Braun, I. and Bretz, T. and Briggs, M. S. and Brun, Pierre and Brunetti, L. and Buckley, H. and Bugaev, V. and Buehler, R. and Bulik, Tomasz and Busetto, G. and Buson, S. and Byrum, K. and Cailles, M. and Cameron, R. A. and Canestrari, R. and Cantu, S. and Carmona, E. and Carosi, A. and Carr, John and Carton, P. H. and Casiraghi, M. and Castarede, H. and Catalano, O. and Cavazzani, S. and Cazaux, S. and Cerruti, B. and Cerruti, M. and Chadwick, M. and Chiang, J. and Chikawa, M. and Cieslar, M. and Ciesielska, M. and Cillis, A. N. and Clerc, C. and Colin, P. and Colome, J. and Compin, M. and Conconi, P. and Connaughton, V. and Conrad, Jan and Contreras, J. L. and Coppi, P. and Corlier, M. and Corona, P. and Corpace, O. and Corti, D. and Cortina, J. and Costantini, H. and Cotter, G. and Courty, B. and Couturier, S. and Covino, S. and Croston, J. and Cusumano, G. and Daniel, M. K. and Dazzi, F. and Deangelis, A. and de Cea del Pozo, E. and Dal Pino, E. M. de Gouveia and de Jager, O. and de la Calle Perez, I. and De La Vega, G. and De Lotto, B. and de Naurois, M. and Wilhelmi, E. de Ona and de Souza, V. and Decerprit, B. and Deil, C. and Delagnes, E. and Deleglise, G. and Delgado, C. and Dettlaff, T. and Di Paolo, A. and Di Pierro, F. and Diaz, C. and Dick, J. and Dickinson, H. and Digel, S. W. and Dimitrov, D. and Disset, G. and Djannati-Ata{\"i}, A. and Doert, M. and Domainko, W. and Dorner, D. and Doro, M. and Dournaux, J. -L. and Dravins, D. and Drury, L. and Dubois, F. and Dubois, R. and Dubus, G. and Dufour, C. and Durand, D. and Dyks, J. and Dyrda, M. and Edy, E. and Egberts, Kathrin and Eleftheriadis, C. and Elles, S. and Emmanoulopoulos, D. and Enomoto, R. and Ernenwein, J. -P. and Errando, M. and Etchegoyen, A. and Falcone, A. D. and Farakos, K. and Farnier, C. and Federici, S. and Feinstein, F. and Ferenc, D. and Fillin-Martino, E. and Fink, D. and Finley, C. and Finley, J. P. and Firpo, R. and Florin, D. and Foehr, C. and Fokitis, E. and Font, Ll. and Fontaine, G. and Fontana, A. and Foerster, A. and Fortson, L. and Fouque, N. and Fransson, C. and Fraser, G. W. and Fresnillo, L. and Fruck, C. and Fujita, Y. and Fukazawa, Y. and Funk, S. and Gaebele, W. and Gabici, S. and Gadola, A. and Galante, N. and Gallant, Y. and Garcia, B. and Garcia Lopez, R. J. and Garrido, D. and Garrido, L. and Gascon, D. and Gasq, C. and Gaug, M. and Gaweda, J. and Geffroy, N. and Ghag, C. and Ghedina, A. and Ghigo, M. and Gianakaki, E. and Giarrusso, S. and Giavitto, G. and Giebels, B. and Giro, E. and Giubilato, P. and Glanzman, T. and Glicenstein, J. -F. and Gochna, M. and Golev, V. and Gomez Berisso, M. and Gonzalez, A. and Gonzalez, F. and Granena, F. and Graciani, R. and Granot, J. and Gredig, R. and Green, A. and Greenshaw, T. and Grimm, O. and Grube, J. and Grudzinska, M. and Grygorczuk, J. and Guarino, V. and Guglielmi, L. and Guilloux, F. and Gunji, S. and Gyuk, G. and Hadasch, D. and Haefner, D. and Hagiwara, R. and Hahn, J. and Hallgren, A. and Hara, S. and Hardcastle, M. J. and Hassan, T. and Haubold, T. and Hauser, M. and Hayashida, M. and Heller, R. and Henri, G. and Hermann, G. and Herrero, A. and Hinton, James Anthony and Hoffmann, D. and Hofmann, W. and Hofverberg, P. and Horns, D. and Hrupec, D. and Huan, H. and Huber, B. and Huet, J. -M. and Hughes, G. and Hultquist, K. and Humensky, T. B. and Huppert, J. -F. and Ibarra, A. and Illa, J. M. and Ingjald, J. and Inoue, S. and Inoue, Y. and Ioka, K. and Jablonski, C. and Jacholkowska, A. and Janiak, M. and Jean, P. and Jensen, H. and Jogler, T. and Jung, I. and Kaaret, P. and Kabuki, S. and Kakuwa, J. and Kalkuhl, C. and Kankanyan, R. and Kapala, M. and Karastergiou, A. and Karczewski, M. and Karkar, S. and Karlsson, N. and Kasperek, J. and Katagiri, H. and Katarzynski, K. and Kawanaka, N. and Kedziora, B. and Kendziorra, E. and Khelifi, B. and Kieda, D. and Kifune, T. and Kihm, T. and Klepser, S. and Kluzniak, W. and Knapp, J. and Knappy, A. R. and Kneiske, T. and Knoedlseder, J. and Koeck, F. and Kodani, K. and Kohri, K. and Kokkotas, K. and Komin, N. and Konopelko, A. and Kosack, K. and Kossakowski, R. and Kostka, P. and Kotula, J. and Kowal, G. and Koziol, J. and Kraehenbuehl, T. and Krause, J. and Krawczynski, H. and Krennrich, F. and Kretzschmann, A. and Kubo, H. and Kudryavtsev, V. A. and Kushida, J. and La Barbera, N. and La Parola, V. and La Rosa, G. and Lopez, A. and Lamanna, G. and Laporte, P. and Lavalley, C. and Le Flour, T. and Le Padellec, A. and Lenain, J. -P. and Lessio, L. and Lieunard, B. and Lindfors, E. and Liolios, A. and Lohse, T. and Lombardi, S. and Lopatin, A. and Lorenz, E. and Lubinski, P. and Luz, O. and Lyard, E. and Maccarone, M. 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L. and Naumann, D. and Nayman, P. and Nedbal, D. and Niedzwiecki, A. and Niemiec, J. and Nikolaidis, A. and Nishijima, K. and Nolan, S. J. and Nowak, N. and O'Brien, P. T. and Ochoa, I. and Ohira, Y. and Ohishi, M. and Ohka, H. and Okumura, A. and Olivetto, C. and Ong, R. A. and Orito, R. and Orr, M. and Osborne, J. P. and Ostrowski, M. and Otero, L. and Otte, A. N. and Ovcharov, E. and Oya, I. and Ozieblo, A. and Paiano, S. and Pallota, J. and Panazol, J. L. and Paneque, D. and Panter, M. and Paoletti, R. and Papyan, G. and Paredes, J. M. and Pareschi, G. and Parsons, R. D. and Arribas, M. Paz and Pedaletti, G. and Pepato, A. and Persic, M. and Petrucci, P. O. and Peyaud, B. and Piechocki, W. and Pita, S. and Pivato, G. and Platos, L. and Platzer, R. and Pogosyan, L. and Pohl, Martin and Pojmanski, G. and Ponz, J. 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M. and Sanuy, A. and Sapozhnikov, L. and Sarkar, S. and Scalzotto, V. and Scapin, V. and Scarcioffolo, M. and Schanz, T. and Schlenstedt, S. and Schlickeiser, R. and Schmidt, T. and Schmoll, J. and Schroedter, M. and Schultz, C. and Schultze, J. and Schulz, A. and Schwanke, U. and Schwarzburg, S. and Schweizer, T. and Seiradakis, J. and Selmane, S. and Seweryn, K. and Shayduk, M. and Shellard, R. C. and Shibata, T. and Sikora, M. and Silk, J. and Sillanpaa, A. and Sitarek, J. and Skole, C. and Smith, N. and Sobczynska, D. and Sofo Haro, M. and Sol, H. and Spanier, F. and Spiga, D. and Spyrou, S. and Stamatescu, V. and Stamerra, A. and Starling, R. L. C. and Stawarz, L. and Steenkamp, R. and Stegmann, Christian and Steiner, S. and Stergioulas, N. and Sternberger, R. and Stinzing, F. and Stodulski, M. and Straumann, U. and Suarez, A. and Suchenek, M. and Sugawara, R. and Sulanke, K. H. and Sun, S. and Supanitsky, A. D. and Sutcliffe, P. and Szanecki, M. and Szepieniec, T. and Szostek, A. and Szymkowiak, A. and Tagliaferri, G. and Tajima, H. and Takahashi, H. and Takahashi, K. and Takalo, L. and Takami, H. and Talbot, R. G. and Tam, P. H. and Tanaka, M. and Tanimori, T. and Tavani, M. and Tavernet, J. -P. and Tchernin, C. and Tejedor, L. A. and Telezhinsky, Igor O. and Temnikov, P. and Tenzer, C. and Terada, Y. and Terrier, R. and Teshima, M. and Testa, V. and Tibaldo, L. and Tibolla, O. and Tluczykont, M. and Peixoto, C. J. Todero and Tokanai, F. and Tokarz, M. and Toma, K. and Torres, D. F. and Tosti, G. and Totani, T. and Toussenel, F. and Vallania, P. and Vallejo, G. and van der Walt, J. and van Eldik, C. and Vandenbroucke, J. and Vankov, H. and Vasileiadis, G. and Vassiliev, V. V. and Vegas, I. and Venter, L. and Vercellone, S. and Veyssiere, C. and Vialle, J. P. and Videla, M. and Vincent, P. and Vink, J. and Vlahakis, N. and Vlahos, L. and Vogler, P. and Vollhardt, A. and Volpe, F. and Von Gunten, H. P. and Vorobiov, S. and Wagner, S. and Wagner, R. M. and Wagner, B. and Wakely, S. P. and Walter, P. and Walter, R. and Warwick, R. and Wawer, P. and Wawrzaszek, R. and Webb, N. and Wegner, P. and Weinstein, A. and Weitzel, Q. and Welsing, R. and Wetteskind, H. and White, R. and Wierzcholska, A. and Wilkinson, M. I. and Williams, D. A. and Winde, M. and Wischnewski, R. and Wisniewski, L. and Wolczko, A. and Wood, M. and Xiong, Q. and Yamamoto, T. and Yamaoka, K. and Yamazaki, R. and Yanagita, S. and Yoffo, B. and Yonetani, M. and Yoshida, A. and Yoshida, T. and Yoshikoshi, T. and Zabalza, V. and Zagdanski, A. and Zajczyk, A. and Zdziarski, A. and Zech, Alraune and Zietara, K. and Ziolkowski, P. and Zitelli, V. and Zychowski, P.}, title = {Design concepts for the Cherenkov Telescope Array CTA an advanced facility for ground-based high-energy gamma-ray astronomy}, series = {Experimental astronomy : an international journal on astronomical instrumentation and data analysis}, volume = {32}, journal = {Experimental astronomy : an international journal on astronomical instrumentation and data analysis}, number = {3}, publisher = {Springer}, address = {Dordrecht}, organization = {CTA Consortium}, issn = {0922-6435}, doi = {10.1007/s10686-011-9247-0}, pages = {193 -- 316}, year = {2011}, abstract = {Ground-based gamma-ray astronomy has had a major breakthrough with the impressive results obtained using systems of imaging atmospheric Cherenkov telescopes. Ground-based gamma-ray astronomy has a huge potential in astrophysics, particle physics and cosmology. CTA is an international initiative to build the next generation instrument, with a factor of 5-10 improvement in sensitivity in the 100 GeV-10 TeV range and the extension to energies well below 100 GeV and above 100 TeV. CTA will consist of two arrays (one in the north, one in the south) for full sky coverage and will be operated as open observatory. The design of CTA is based on currently available technology. This document reports on the status and presents the major design concepts of CTA.}, language = {en} } @article{AliuArchambaultArlenetal.2012, author = {Aliu, E. and Archambault, S. and Arlen, T. and Aune, T. and Beilicke, M. and Benbow, W. and Bouvier, A. and Buckley, J. H. and Bugaev, V. and Byrum, K. and Cesarini, A. and Ciupik, L. and Collins-Hughes, E. and Connolly, M. P. and Cui, W. and Dickherber, R. and Duke, C. and Dumm, J. and Falcone, A. and Federici, S. and Feng, Q. and Finley, J. P. and Finnegan, G. and Fortson, L. and Furniss, A. and Galante, N. and Gall, D. and Gillanders, G. H. and Godambe, S. and Griffin, S. and Grube, J. and Gyuk, G. and Hanna, D. and Holder, J. and Huan, H. and Hughes, G. and Humensky, T. B. and Kaaret, P. and Karlsson, N. and Khassen, Y. and Kieda, D. and Krawczynski, H. and Krennrich, F. and Lang, M. J. and LeBohec, S. and Lee, K. and Lyutikov, M. and Madhavan, A. S. and Maier, G. and Majumdar, P. and McArthur, S. and McCann, A. and Moriarty, P. and Mukherjee, R. and Nelson, T. and de Bhroithe, A. O'Faolain and Ong, R. A. and Orr, M. and Otte, A. N. and Park, N. and Perkins, J. S. and Pohl, M. and Prokoph, H. and Quinn, J. and Ragan, K. and Reyes, L. C. and Reynolds, P. T. and Roache, E. and Saxon, D. B. and Schr{\"o}dter, M. and Sembroski, G. H. and Sentuerk, G. D. and Smith, A. W. and Staszak, D. and Telezhinsky, Igor O. and Tesic, G. and Theiling, M. and Thibadeau, S. and Tsurusaki, K. and Varlotta, A. and Vincent, S. and Vivier, M. and Wagner, R. G. and Wakely, S. P. and Weekes, T. C. and Weinstein, A. and Welsing, R. and Williams, D. A. and Zitzer, B. and Kondratiev, V.}, title = {SEARCH FOR A CORRELATION BETWEEN VERY-HIGH-ENERGY GAMMA RAYS AND GIANT RADIO PULSES IN THE CRAB PULSAR}, series = {The astrophysical journal : an international review of spectroscopy and astronomical physics}, volume = {760}, journal = {The astrophysical journal : an international review of spectroscopy and astronomical physics}, number = {2}, publisher = {IOP Publ. Ltd.}, address = {Bristol}, issn = {0004-637X}, doi = {10.1088/0004-637X/760/2/136}, pages = {13}, year = {2012}, abstract = {We present the results of a joint observational campaign between the Green Bank radio telescope and the VERITAS gamma-ray telescope, which searched for a correlation between the emission of very-high-energy (VHE) gamma rays (E-gamma > 150 GeV) and giant radio pulses (GRPs) from the Crab pulsar at 8.9 GHz. A total of 15,366 GRPs were recorded during 11.6 hr of simultaneous observations, which were made across four nights in 2008 December and in 2009 November and December. We searched for an enhancement of the pulsed gamma-ray emission within time windows placed around the arrival time of the GRP events. In total, eight different time windows with durations ranging from 0.033 ms to 72 s were positioned at three different locations relative to the GRP to search for enhanced gamma-ray emission which lagged, led, or was concurrent with, the GRP event. Furthermore, we performed separate searches on main pulse GRPs and interpulse GRPs and on the most energetic GRPs in our data sample. No significant enhancement of pulsed VHE emission was found in any of the preformed searches. We set upper limits of 5-10 times the average VHE flux of the Crab pulsar on the flux simultaneous with interpulse GRPs on single-rotation-period timescales. On similar to 8 s timescales around interpulse GRPs, we set an upper limit of 2-3 times the average VHE flux. Within the framework of recent models for pulsed VHE emission from the Crab pulsar, the expected VHE-GRP emission correlations are below the derived limits.}, language = {en} } @article{AliuArchambaultArlenetal.2012, author = {Aliu, E. and Archambault, S. and Arlen, T. and Aune, T. and Beilicke, M. and Benbow, W. and Bouvier, A. and Bradbury, S. M. and Buckley, J. H. and Bugaev, V. and Byrum, K. and Cannon, A. and Cesarini, A. and Ciupik, L. and Collins-Hughes, E. and Connolly, M. P. and Cui, W. and Decerprit, G. and Dickherber, R. and Duke, C. and Dumm, J. and Dwarkadas, Vikram V. and Errando, M. and Falcone, A. and Feng, Q. and Finley, J. P. and Finnegan, G. and Fortson, L. and Furniss, A. and Galante, N. and Gall, D. and Godambe, S. and Griffin, S. and Grube, J. and Gyuk, G. and Hanna, D. and Holder, J. and Huan, H. and Hughes, G. and Humensky, T. B. and Kaaret, P. and Karlsson, N. and Kertzman, M. and Khassen, Y. and Kieda, D. and Krawczynski, H. and Krennrich, F. and Lang, M. J. and Lee, K. and Maier, G. and Majumdar, P. and McArthur, S. and McCann, A. and Millis, J. and Moriarty, P. and Mukherjee, R. and Nunez, P. D. and Ong, R. A. and Orr, M. and Otte, A. N. and Pandel, D. and Park, N. and Perkins, J. S. and Pohl, M. and Prokoph, H. and Quinn, J. and Ragan, K. and Reyes, L. C. and Reynolds, P. T. and Roache, E. and Rose, H. J. and Ruppel, J. and Saxon, D. B. and Schroedter, M. and Sembroski, G. H. and Skole, C. and Smith, A. W. and Staszak, D. and Telezhinsky, Igor O. and Tesic, G. and Theiling, M. and Thibadeau, S. and Tsurusaki, K. and Tyler, J. and Varlotta, A. and Vincent, S. and Vivier, M. and Wakely, S. P. and Ward, J. E. and Weekes, T. C. and Weinstein, A. and Weisgarber, T. and Welsing, R. and Williams, D. A. and Zitzer, B.}, title = {Veritas observations of the nova in V407 CYGNI}, series = {The astrophysical journal : an international review of spectroscopy and astronomical physics}, volume = {754}, journal = {The astrophysical journal : an international review of spectroscopy and astronomical physics}, number = {1}, publisher = {IOP Publ. Ltd.}, address = {Bristol}, issn = {0004-637X}, doi = {10.1088/0004-637X/754/1/77}, pages = {7}, year = {2012}, abstract = {We report on very high energy (E > 100 GeV) gamma-ray observations of V407 Cygni, a symbiotic binary that underwent a nova outburst producing 0.1-10 GeV gamma rays during 2010 March 10-26. Observations were made with the Very Energetic Radiation Imaging Telescope Array System during 2010 March 19-26 at relatively large zenith angles due to the position of V407 Cyg. An improved reconstruction technique for large zenith angle observations is presented and used to analyze the data. We do not detect V407 Cygni and place a differential upper limit on the flux at 1.6 TeV of 2.3 x 10(-12) erg cm(-2) s(-1) (at the 95\% confidence level). When considered jointly with data from Fermi-LAT, this result places limits on the acceleration of very high energy particles in the nova.}, language = {en} } @article{AbramowskiAceroAharonianetal.2012, author = {Abramowski, Attila and Acero, F. and Aharonian, Felix A. and Akhperjanian, A. G. and Anton, Gisela and Balzer, Arnim and Barnacka, Anna and de Almeida, U. Barres and Becherini, Yvonne and Becker, J. and Behera, B. and Bernl{\"o}hr, K. and Birsin, E. and Biteau, Jonathan and Bochow, A. and Boisson, Catherine and Bolmont, J. and Bordas, Pol and Brucker, J. and Brun, Francois and Brun, Pierre and Bulik, Tomasz and Buesching, I. and Carrigan, Svenja and Casanova, Sabrina and Cerruti, M. and Chadwick, Paula M. and Charbonnier, A. and Chaves, Ryan C. G. and Cheesebrough, A. and Clapson, A. C. and Coignet, G. and Cologna, Gabriele and Conrad, Jan and Dalton, M. and Daniel, M. K. and Davids, I. D. and Degrange, B. and Deil, C. and Dickinson, H. J. and Djannati-Ata{\"i}, A. and Domainko, W. and Drury, L. O'C. and Dubus, G. and Dutson, K. and Dyks, J. and Dyrda, M. and Egberts, Kathrin and Eger, P. and Espigat, P. and Fallon, L. and Farnier, C. and Fegan, S. and Feinstein, F. and Fernandes, M. V. and Fiasson, A. and Fontaine, G. and Foerster, A. and Fuessling, M. and Gallant, Y. A. and Gast, H. and Gerard, L. and Gerbig, D. and Giebels, B. and Glicenstein, J. F. and Glueck, B. and Goret, P. and Goering, D. and Haeffner, S. and Hague, J. D. and Hampf, D. and Hauser, M. and Heinz, S. and Heinzelmann, G. and Henri, G. and Hermann, G. and Hinton, James Anthony and Hoffmann, A. and Hofmann, W. and Hofverberg, P. and Holler, M. and Horns, D. and Jacholkowska, A. and de Jager, O. C. and Jahn, C. and Jamrozy, M. and Jung, I. and Kastendieck, M. A. and Katarzynski, K. and Katz, U. and Kaufmann, S. and Keogh, D. and Khangulyan, D. and Khelifi, B. and Klochkov, D. and Kluzniak, W. and Kneiske, T. and Komin, Nu. and Kosack, K. and Kossakowski, R. and Laffon, H. and Lamanna, G. and Lennarz, D. and Lohse, T. and Lopatin, A. and Lu, C. -C. and Marandon, V. and Marcowith, A. and Masbou, J. and Maurin, D. and Maxted, N. and Mayer, M. and McComb, T. J. L. and Medina, M. C. and Mehault, J. and Moderski, R. and Moulin, E. and Naumann, C. L. and Naumann-Godo, M. and de Naurois, M. and Nedbal, D. and Nekrassov, D. and Nguyen, N. and Nicholas, B. and Niemiec, J. and Nolan, S. J. and Ohm, S. and Wilhelmi, E. de Ona and Opitz, B. and Ostrowski, M. and Oya, I. and Panter, M. and Arribas, M. Paz and Pedaletti, G. and Pelletier, G. and Petrucci, P. -O. and Pita, S. and Puehlhofer, G. and Punch, M. and Quirrenbach, A. and Raue, M. and Rayner, S. M. and Reimer, A. and Reimer, O. and Renaud, M. and de los Reyes, R. and Rieger, F. and Ripken, J. and Rob, L. and Rosier-Lees, S. and Rowell, G. and Rudak, B. and Rulten, C. B. and Ruppel, J. and Sahakian, V. and Sanchez, David M. and Santangelo, A. and Schlickeiser, R. and Schoeck, F. M. and Schulz, A. and Schwanke, U. and Schwarzburg, S. and Schwemmer, S. and Sheidaei, F. and Skilton, J. L. and Sol, H. and Spengler, G. and Stawarz, L. and Steenkamp, R. and Stegmann, Christian and Stinzing, F. and Stycz, K. and Sushch, Iurii and Szostek, A. and Tavernet, J. -P. and Terrier, R. and Tluczykont, M. and Valerius, K. and van Eldik, C. and Vasileiadis, G. and Venter, C. and Vialle, J. P. and Viana, A. and Vincent, P. and Voelk, H. J. and Volpe, F. and Vorobiov, S. and Vorster, M. and Wagner, S. J. and Ward, M. and White, R. and Wierzcholska, A. and Zacharias, M. and Zajczyk, A. and Zdziarski, A. A. and Zech, Alraune and Zechlin, H. -S. and Aleksic, J. and Antonelli, L. A. and Antoranz, P. and Backes, Michael and Barrio, J. A. and Bastieri, D. and Becerra Gonzalez, J. and Bednarek, W. and Berdyugin, A. and Berger, K. and Bernardini, E. and Biland, A. and Blanch Bigas, O. and Bock, R. K. and Boller, A. and Bonnoli, G. and Tridon, D. Borla and Braun, I. and Bretz, T. and Canellas, A. and Carmona, E. and Carosi, A. and Colin, P. and Colombo, E. and Contreras, J. L. and Cortina, J. and Cossio, L. and Covino, S. and Dazzi, F. and De Angelis, A. and De Cea del Pozo, E. and De Lotto, B. and Delgado Mendez, C. and Diago Ortega, A. and Doert, M. and Dominguez, A. and Prester, Dijana Dominis and Dorner, D. and Doro, M. and Elsaesser, D. and Ferenc, D. and Fonseca, M. V. and Font, L. and Fruck, C. and Garcia Lopez, R. J. and Garczarczyk, M. and Garrido, D. and Giavitto, G. and Godinovic, N. and Hadasch, D. and Haefner, D. and Herrero, A. and Hildebrand, D. and Hoehne-Moench, D. and Hose, J. and Hrupec, D. and Huber, B. and Jogler, T. and Klepser, S. and Kraehenbuehl, T. and Krause, J. and La Barbera, A. and Lelas, D. and Leonardo, E. and Lindfors, E. and Lombardi, S. and Lopez, M. and Lorenz, E. and Makariev, M. and Maneva, G. and Mankuzhiyil, N. and Mannheim, K. and Maraschi, L. and Mariotti, M. and Martinez, M. and Mazin, D. and Meucci, M. and Miranda, J. M. and Mirzoyan, R. and Miyamoto, H. and Moldon, J. and Moralejo, A. and Munar, P. and Nieto, D. and Nilsson, K. and Orito, R. and Oya, I. and Paneque, D. and Paoletti, R. and Pardo, S. and Paredes, J. M. and Partini, S. and Pasanen, M. and Pauss, F. and Perez-Torres, M. A. and Persic, M. and Peruzzo, L. and Pilia, M. and Pochon, J. and Prada, F. and Moroni, P. G. Prada and Prandini, E. and Puljak, I. and Reichardt, I. and Reinthal, R. and Rhode, W. and Ribo, M. and Rico, J. and Ruegamer, S. and Saggion, A. and Saito, K. and Saito, T. Y. and Salvati, M. and Satalecka, K. and Scalzotto, V. and Scapin, V. and Schultz, C. and Schweizer, T. and Shayduk, M. and Shore, S. N. and Sillanpaa, A. and Sitarek, J. and Sobczynska, D. and Spanier, F. and Spiro, S. and Stamerra, A. and Steinke, B. and Storz, J. and Strah, N. and Suric, T. and Takalo, L. and Takami, H. and Tavecchio, F. and Temnikov, P. and Terzic, T. and Tescaro, D. and Teshima, M. and Thom, M. and Tibolla, O. and Torres, D. F. and Treves, A. and Vankov, H. and Vogler, P. and Wagner, R. M. and Weitzel, Q. and Zabalza, V. and Zandanel, F. and Zanin, R. and Arlen, T. and Aune, T. and Beilicke, M. and Benbow, W. and Bouvier, A. and Bradbury, S. M. and Buckley, J. H. and Bugaev, V. and Byrum, K. and Cannon, A. and Cesarini, A. and Ciupik, L. and Connolly, M. P. and Cui, W. and Dickherber, R. and Duke, C. and Errando, M. and Falcone, A. and Finley, J. P. and Finnegan, G. and Fortson, L. and Furniss, A. and Galante, N. and Gall, D. and Godambe, S. and Griffin, S. and Grube, J. and Gyuk, G. and Hanna, D. and Holder, J. and Huan, H. and Hui, C. M. and Kaaret, P. and Karlsson, N. and Kertzman, M. and Khassen, Y. and Kieda, D. and Krawczynski, H. and Krennrich, F. and Lang, M. J. and LeBohec, S. and Maier, G. and McArthur, S. and McCann, A. and Moriarty, P. and Mukherjee, R. and Nunez, P. D. and Ong, R. A. and Orr, M. and Otte, A. N. and Park, N. and Perkins, J. S. and Pichel, A. and Pohl, Martin and Prokoph, H. and Ragan, K. and Reyes, L. C. and Reynolds, P. T. and Roache, E. and Rose, H. J. and Ruppel, J. and Schroedter, M. and Sembroski, G. H. and Sentuerk, G. D. and Telezhinsky, Igor O. and Tesic, G. and Theiling, M. and Thibadeau, S. and Varlotta, A. and Vassiliev, V. V. and Vivier, M. and Wakely, S. P. and Weekes, T. C. and Williams, D. A. and Zitzer, B. and de Almeida, U. Barres and Cara, M. and Casadio, C. and Cheung, C. C. and McConville, W. and Davies, F. and Doi, A. and Giovannini, G. and Giroletti, M. and Hada, K. and Hardee, P. and Harris, D. E. and Junor, W. and Kino, M. and Lee, N. P. and Ly, C. and Madrid, J. and Massaro, F. and Mundell, C. G. and Nagai, H. and Perlman, E. S. and Steele, I. A. and Walker, R. C. and Wood, D. L.}, title = {The 2010 very high energy gamma-ray flare and 10 years ofmulti-wavelength oservations of M 87}, series = {The astrophysical journal : an international review of spectroscopy and astronomical physics}, volume = {746}, journal = {The astrophysical journal : an international review of spectroscopy and astronomical physics}, number = {2}, publisher = {IOP Publ. Ltd.}, address = {Bristol}, organization = {HESS Collaboration, MAGIC Collaboration, VERITAS Collaboration}, issn = {0004-637X}, doi = {10.1088/0004-637X/746/2/151}, pages = {18}, year = {2012}, abstract = {The giant radio galaxy M 87 with its proximity (16 Mpc), famous jet, and very massive black hole ((3-6) x 10(9) M-circle dot) provides a unique opportunity to investigate the origin of very high energy (VHE; E > 100 GeV) gamma-ray emission generated in relativistic outflows and the surroundings of supermassive black holes. M 87 has been established as a VHE gamma-ray emitter since 2006. The VHE gamma-ray emission displays strong variability on timescales as short as a day. In this paper, results from a joint VHE monitoring campaign on M 87 by the MAGIC and VERITAS instruments in 2010 are reported. During the campaign, a flare at VHE was detected triggering further observations at VHE (H.E.S.S.), X-rays (Chandra), and radio (43 GHz Very Long Baseline Array, VLBA). The excellent sampling of the VHE gamma-ray light curve enables one to derive a precise temporal characterization of the flare: the single, isolated flare is well described by a two-sided exponential function with significantly different flux rise and decay times of tau(rise)(d) = (1.69 +/- 0.30) days and tau(decay)(d) = (0.611 +/- 0.080) days, respectively. While the overall variability pattern of the 2010 flare appears somewhat different from that of previous VHE flares in 2005 and 2008, they share very similar timescales (similar to day), peak fluxes (Phi(>0.35 TeV) similar or equal to (1-3) x 10(-11) photons cm(-2) s(-1)), and VHE spectra. VLBA radio observations of 43 GHz of the inner jet regions indicate no enhanced flux in 2010 in contrast to observations in 2008, where an increase of the radio flux of the innermost core regions coincided with a VHE flare. On the other hand, Chandra X-ray observations taken similar to 3 days after the peak of the VHE gamma-ray emission reveal an enhanced flux from the core (flux increased by factor similar to 2; variability timescale <2 days). The long-term (2001-2010) multi-wavelength (MWL) light curve of M 87, spanning from radio to VHE and including data from Hubble Space Telescope, Liverpool Telescope, Very Large Array, and European VLBI Network, is used to further investigate the origin of the VHE gamma-ray emission. No unique, common MWL signature of the three VHE flares has been identified. In the outer kiloparsec jet region, in particular in HST-1, no enhanced MWL activity was detected in 2008 and 2010, disfavoring it as the origin of the VHE flares during these years. Shortly after two of the three flares (2008 and 2010), the X-ray core was observed to be at a higher flux level than its characteristic range (determined from more than 60 monitoring observations: 2002-2009). In 2005, the strong flux dominance of HST-1 could have suppressed the detection of such a feature. Published models for VHE gamma-ray emission from M 87 are reviewed in the light of the new data.}, language = {en} } @article{AliuArchambaultArlenetal.2012, author = {Aliu, E. and Archambault, S. and Arlen, T. and Aune, T. and Beilicke, M. and Benbow, W. and Boettcher, Markus and Bouvier, A. and Bradbury, S. M. and Buckley, J. H. and Bugaev, V. and Byrum, K. and Cannon, A. and Cesarini, A. and Ciupik, L. and Collins-Hughes, E. and Connolly, M. P. and Coppi, P. and Cui, W. and Decerprit, G. and Dickherber, R. and Dumm, J. and Errando, Manel and Falcone, A. and Feng, Q. and Finley, J. P. and Finnegan, G. and Fortson, L. and Furniss, A. and Galante, N. and Gall, D. and Godambe, S. and Griffin, S. and Grube, J. and Gyuk, G. and Hanna, D. and Hawkins, K. and Holder, J. and Huan, H. and Hughes, G. and Humensky, T. B. and Kaaret, P. and Karlsson, N. and Kertzman, M. and Khassen, Y. and Kieda, D. and Krawczynski, H. and Krennrich, F. and Lang, M. J. and Lee, K. and Madhavan, A. S. and Maier, G. and Majumdar, P. and McArthur, S. and McCann, A. and Moriarty, P. and Mukherjee, Reshmi and Ong, R. A. and Orr, M. and Otte, A. N. and Palma, N. and Park, N. and Perkins, J. S. and Pichel, A. and Pohl, Martin and Prokoph, H. and Quinn, J. and Ragan, K. and Reyes, L. C. and Reynolds, P. T. and Roache, E. and Rose, H. J. and Ruppel, J. and Saxon, D. B. and Schroedter, M. and Sembroski, G. H. and Sentuerk, G. D. and Smith, A. W. and Staszak, D. and Telezhinsky, Igor O. and Tesic, G. and Theiling, M. and Thibadeau, S. and Tsurusaki, K. and Varlotta, A. and Vivier, M. and Wakely, S. P. and Ward, J. E. and Weekes, T. C. and Weinstein, A. and Weisgarber, T. and Williams, D. A. and Zitzer, B. and Fortin, P. and Horan, D.}, title = {Disovery of high-energy and very high energy gamma-ray emission from the blazar RBS 0413}, series = {The astrophysical journal : an international review of spectroscopy and astronomical physics}, volume = {750}, journal = {The astrophysical journal : an international review of spectroscopy and astronomical physics}, number = {2}, publisher = {IOP Publ. Ltd.}, address = {Bristol}, issn = {0004-637X}, doi = {10.1088/0004-637X/750/2/94}, pages = {6}, year = {2012}, abstract = {We report on the discovery of high-energy (HE; E > 0.1 GeV) and very high energy (VHE; E > 100 GeV) gamma-ray emission from the high-frequency-peaked BL Lac object RBS 0413. VERITAS, a ground-based gamma-ray observatory, detected VHE. rays from RBS 0413 with a statistical significance of 5.5 standard deviations (sigma) and a gamma-ray flux of (1.5 +/- 0.6(stat) +/- 0.7(syst)) x 10(-8) photons m(-2) s(-1) (similar to 1\% of the Crab Nebula flux) above 250 GeV. The observed spectrum can be described by a power law with a photon index of 3.18 +/- 0.68(stat) +/- 0.30(syst). Contemporaneous observations with the Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope detected HE gamma rays from RBS 0413 with a (stat)istical significance of more than 9 sigma, a power-law photon index of 1.57 +/- 0.12(stat-0.12sys')(+0.11) and a gamma-ray flux between 300 MeV and 300 GeV of (1.64 +/- 0.43(stat-0.22sys)(+ 0.31)) x 10(-5) photons m(-2) s(-1). We present the results from Fermi-LAT and VERITAS, including a spectral energy distribution modeling of the gamma-ray, quasi-simultaneous X-ray (Swift-XRT), ultraviolet (Swift-UVOT), and R-band optical (MDM) data. We find that, if conditions close to equipartition are required, both the combined synchrotron self-Compton/external-Compton and the lepto-hadronic models are preferred over a pure synchrotron self-Compton model.}, language = {en} } @article{AliuArchambaultArlenetal.2012, author = {Aliu, E. and Archambault, S. and Arlen, T. and Aune, T. and Beilicke, M. and Benbow, W. and Boettcher, Markus and Bouvier, A. and Buckley, J. H. and Bugaev, V. and Cesarini, A. and Ciupik, L. and Collins-Hughes, E. and Connolly, M. P. and Cui, W. and Dickherber, R. and Duke, C. and Dumm, J. and Errando, M. and Falcone, A. and Federici, Simone and Feng, Q. and Finley, J. P. and Finnegan, G. and Fortson, L. and Furniss, A. and Galante, N. and Gall, D. and Godambe, S. and Griffin, S. and Grube, J. and Gyuk, G. and Hanna, D. and Holder, J. and Huan, H. and Kaaret, P. and Karlsson, N. and Khassen, Y. and Kieda, D. and Krawczynski, H. and Krennrich, F. and Lee, K. and Madhavan, A. S. and Maier, G. and Majumdar, P. and McArthur, S. and McCann, A. and Moriarty, P. and Mukherjee, R. and Nelson, T. and de Bhroithe, A. O'Faolain and Ong, R. A. and Orr, M. and Otte, A. N. and Park, N. and Perkins, J. S. and Pichel, A. and Pohl, Martin and Prokoph, H. and Quinn, J. and Ragan, K. and Reyes, L. C. and Reynolds, P. T. and Roache, E. and Saxon, D. B. and Sembroski, G. H. and Staszak, D. and Telezhinsky, Igor O. and Tesic, G. and Theiling, M. and Thibadeau, S. and Tsurusaki, K. and Varlotta, A. and Vassiliev, V. V. and Vincent, S. and Vivier, M. and Wakely, S. P. and Weekes, T. C. and Weinstein, A. and Welsing, R. and Williams, D. A. and Zitzer, B. and Fortin, P. and Horan, D. and Fumagalli, M. and Kaplan, K. and Prochaska, J. X.}, title = {Veritas observations of six bright, hard-spectrum fermi-lat blazars}, series = {The astrophysical journal : an international review of spectroscopy and astronomical physics}, volume = {759}, journal = {The astrophysical journal : an international review of spectroscopy and astronomical physics}, number = {2}, publisher = {IOP Publ. Ltd.}, address = {Bristol}, organization = {VERITAS Collaboration}, issn = {0004-637X}, doi = {10.1088/0004-637X/759/2/102}, pages = {13}, year = {2012}, abstract = {We report on VERITAS very high energy (VHE; E >= 100 GeV) observations of six blazars selected from the Fermi Large Area Telescope First Source Catalog (1FGL). The gamma-ray emission from 1FGL sources was extrapolated up to the VHE band, taking gamma-ray absorption by the extragalactic background light into account. This allowed the selection of six bright, hard-spectrum blazars that were good candidate TeV emitters. Spectroscopic redshift measurements were attempted with the Keck Telescope for the targets without Sloan Digital Sky Survey spectroscopic data. No VHE emission is detected during the observations of the six sources described here. Corresponding TeV upper limits are presented, along with contemporaneous Fermi observations and non-concurrent Swift UVOT and X-Ray Telescope data. The blazar broadband spectral energy distributions (SEDs) are assembled and modeled with a single-zone synchrotron self-Compton model. The SED built for each of the six blazars shows a synchrotron peak bordering between the intermediate-and high-spectrum-peak classifications, with four of the six resulting in particle-dominated emission regions.}, language = {en} } @article{TelezhinskyDwarkadasPohl2012, author = {Telezhinsky, Igor O. and Dwarkadas, Vikram V. and Pohl, Martin}, title = {Particle spectra from acceleration at forward and reverse shocks of young Type Ia Supernova Remnants}, series = {Astroparticle physics}, volume = {35}, journal = {Astroparticle physics}, number = {6}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0927-6505}, doi = {10.1016/j.astropartphys.2011.10.001}, pages = {300 -- 311}, year = {2012}, abstract = {We study cosmic-ray acceleration in young Type Ia Supernova Remnants (SNRs) by means of test-particle diffusive shock acceleration theory and 1-D hydrodynamical simulations of their evolution. In addition to acceleration at the forward shock, we explore the particle acceleration at the reverse shock in the presence of a possible substantial magnetic field, and consequently the impact of this acceleration on the particle spectra in the remnant. We investigate the time evolution of the spectra for various time-dependent profiles of the magnetic field in the shocked region of the remnant. We test a possible influence on particle spectra of the Alfvenic drift of scattering centers in the precursor regions of the shocks. In addition, we study the radiation spectra and morphology in a broad band from radio to gamma-rays. It is demonstrated that the reverse shock contribution to the cosmic-ray particle population of young Type la SNRs may be significant, modifying the spatial distribution of particles and noticeably affecting the volume-integrated particle spectra in young SNRs. In particular spectral structures may arise in test-particle calculations that are often discussed as signatures of non-linear cosmic-ray modification of shocks. Therefore, the spectrum and morphology of emission, and their time evolution, differ from pure forward-shock solutions.}, language = {en} } @article{ArlenAuneBeilickeetal.2012, author = {Arlen, T. and Aune, T. and Beilicke, M. and Benbow, W. and Bouvier, A. and Buckley, J. H. and Bugaev, V. and Byrum, K. and Cannon, A. and Cesarini, A. and Ciupik, L. and Collins-Hughes, E. and Connolly, M. P. and Cui, W. and Dickherber, R. and Dumm, J. and Falcone, A. and Federici, S. and Feng, Q. and Finley, J. P. and Finnegan, G. and Fortson, L. and Furniss, A. and Galante, N. and Gall, D. and Godambe, S. and Griffin, S. and Grube, J. and Gyuk, G. and Holder, J. and Huan, H. and Hughes, G. and Humensky, T. B. and Imran, A. and Kaaret, P. and Karlsson, N. and Kertzman, M. and Khassen, Y. and Kieda, D. and Krawczynski, H. and Krennrich, F. and Lee, K. and Madhavan, A. S. and Maier, G. and Majumdar, P. and McArthur, S. and McCann, A. and Moriarty, P. and Mukherjee, R. and Nelson, T. and de Bhroithe, A. O'Faolain and Ong, R. A. and Orr, M. and Otte, A. N. and Park, N. and Perkins, J. S. and Pohl, Martin and Prokoph, H. and Quinn, J. and Ragan, K. and Reyes, L. C. and Reynolds, P. T. and Roache, E. and Ruppel, J. and Saxon, D. B. and Schroedter, M. and Sembroski, G. H. and Skole, C. and Smith, A. W. and Telezhinsky, Igor O. and Tesic, G. and Theiling, M. and Thibadeau, S. and Tsurusaki, K. and Varlotta, A. and Vivier, M. and Wakely, S. P. and Ward, J. E. and Weinstein, A. and Welsing, R. and Williams, D. A. and Zitzer, B. and Pfrommer, C. and Pinzke, A.}, title = {Constraints on cosmic rays, magnetic fields, and dark matter fromgamma-ray observations of the coma cluster of galaxies with veritas and fermi}, series = {The astrophysical journal : an international review of spectroscopy and astronomical physics}, volume = {757}, journal = {The astrophysical journal : an international review of spectroscopy and astronomical physics}, number = {2}, publisher = {IOP Publ. Ltd.}, address = {Bristol}, issn = {0004-637X}, doi = {10.1088/0004-637X/757/2/123}, pages = {14}, year = {2012}, abstract = {Observations of radio halos and relics in galaxy clusters indicate efficient electron acceleration. Protons should likewise be accelerated and, on account of weak energy losses, can accumulate, suggesting that clusters may also be sources of very high energy (VHE; E > 100 GeV) gamma-ray emission. We report here on VHE gamma-ray observations of the Coma galaxy cluster with the VERITAS array of imaging Cerenkov telescopes, with complementing Fermi Large Area Telescope observations at GeV energies. No significant gamma-ray emission from the Coma Cluster was detected. Integral flux upper limits at the 99\% confidence level were measured to be on the order of (2-5) x 10(-8) photonsm(-2) s(-1) (VERITAS, >220 GeV) and similar to 2 x 10(-6) photonsm(-2) s(-1) (Fermi, 1-3GeV), respectively. We use the gamma-ray upper limits to constrain cosmic rays (CRs) and magnetic fields in Coma. Using an analytical approach, the CR-to-thermal pressure ratio is constrained to be < 16\% from VERITAS data and <1.7\% from Fermi data (averaged within the virial radius). These upper limits are starting to constrain the CR physics in self-consistent cosmological cluster simulations and cap the maximum CR acceleration efficiency at structure formation shocks to be <50\%. Alternatively, this may argue for non-negligible CR transport processes such as CR streaming and diffusion into the outer cluster regions. Assuming that the radio-emitting electrons of the Coma halo result from hadronic CR interactions, the observations imply a lower limit on the central magnetic field in Coma of similar to(2-5.5) mu G, depending on the radial magnetic field profile and on the gamma-ray spectral index. Since these values are below those inferred by Faraday rotation measurements in Coma (for most of the parameter space), this renders the hadronic model a very plausible explanation of the Coma radio halo. Finally, since galaxy clusters are dark matter (DM) dominated, the VERITAS upper limits have been used to place constraints on the thermally averaged product of the total self-annihilation cross section and the relative velocity of the DM particles, .}, language = {en} } @article{AliuArchambaultArlenetal.2012, author = {Aliu, E. and Archambault, S. and Arlen, T. and Aune, T. and Beilicke, M. and Benbow, W. and Boettcher, Markus and Bouvier, A. and Bugaev, V. and Cannon, A. and Cesarini, A. and Ciupik, L. and Collins-Hughes, E. and Connolly, M. P. and Cui, W. and Dickherber, R. and Dumm, J. and Errando, M. and Falcone, A. and Federici, Stefania and Feng, Q. and Finley, J. P. and Finnegan, G. and Fortson, L. and Furniss, A. and Galante, N. and Gall, D. and Godambe, S. and Griffin, S. and Grube, J. and Gyuk, G. and Hanna, D. and Holder, J. and Huan, H. and Hughes, G. and Hui, C. M. and Imran, A. and Jameil, O. and Kaaret, P. and Karlsson, N. and Kertzman, M. and Kerr, J. and Khassen, Y. and Kieda, D. and Krawczynski, H. and Krennrich, F. and Lang, M. J. and Lee, K. and Madhavan, A. S. and Majumdar, P. and McArthur, S. and McCann, A. and Moriarty, P. and Mukherjee, R. and Nelson, T. and de Bhroithe, A. O'Faolain and Ong, R. A. and Orr, M. and Otte, A. N. and Park, N. and Perkins, J. S. and Pichel, A. and Pohl, Martin and Quinn, J. and Ragan, K. and Reynolds, P. T. and Roache, E. and Ruppel, J. and Saxon, D. B. and Schroedter, M. and Sembroski, G. H. and Sentuerk, G. D. and Smith, A. W. and Staszak, D. and Stroh, M. and Telezhinsky, Igor O. and Tesic, G. and Theiling, M. and Thibadeau, S. and Tsurusaki, K. and Varlotta, A. and Vassiliev, V. V. and Vivier, M. and Wakely, S. P. and Ward, J. E. and Weinstein, A. and Welsing, R. and Williams, D. A. and Zitzer, B.}, title = {Multiwavelength observations of the AGN 1ES 0414+009 with veritas, FERMI-LAT, SWIFT-XRT, AND MDM}, series = {The astrophysical journal : an international review of spectroscopy and astronomical physics}, volume = {755}, journal = {The astrophysical journal : an international review of spectroscopy and astronomical physics}, number = {2}, publisher = {IOP Publ. Ltd.}, address = {Bristol}, issn = {0004-637X}, doi = {10.1088/0004-637X/755/2/118}, pages = {7}, year = {2012}, abstract = {We present observations of the BL Lac object 1ES 0414+009 in the >200 GeV gamma-ray band by the VERITAS array of Cherenkov telescopes. 1ES 0414+009 was observed by VERITAS between 2008 January and 2011 February, resulting in 56.2 hr of good quality pointed observations. These observations resulted in a detection of 822 events from the source corresponding to a statistical significance of 6.4 standard deviations (6.4 sigma) above the background. The source flux, showing no evidence for variability, is measured as (5.2 +/- 1.1(stat) +/- 2.6(sys)) x 10(-12) photons cm(-2) s(-1) above 200 GeV, equivalent to approximately 2\% of the Crab Nebula flux above this energy. The differential photon spectrum from 230 GeV to 850 GeV is well fit by a power law with a photon index of Gamma = 3.4 +/- 0.5(stat) +/- 0.3(sys) and a flux normalization of (1.6 +/- 0.3(stat) +/- 0.8(sys)) x 10(-11) photons cm(-2) s(-1) at 300 GeV. We also present multiwavelength results taken in the optical (MDM), x-ray (Swift-XRT), and GeV (Fermi-LAT) bands and use these results to construct a broadband spectral energy distribution (SED). Modeling of this SED indicates that homogenous one-zone leptonic scenarios are not adequate to describe emission from the system, with a lepto-hadronic model providing a better fit to the data.}, language = {en} }