* Astronomy

Title: Discovery of Very High-Energy Gamma-Ray Radiation from the BL Lac 1ES 0806+524
Authors: VERITAS Collaboration: V. Acciari, E. Aliu, T. Arlen, M. Bautista, M. Beilicke, W. Benbow, M. Böttcher, S. M. Bradbury, J. H. Buckley, V. Bugaev, Y. Butt, K. Byrum, A. Cannon, O. Celik, A. Cesarini, Y. C. Chow, L. Ciupik, P. Cogan, P. Colin, W. Cui, R. Dickherber, C. Duke, T. Ergin, A. Falcone, S. J. Fegan, J. P. Finley, G. Finnegan, P. Fortin, L. Fortson, A. Furniss, D. Gall, K. Gibbs, G. H. Gillanders, J. Grube, R. Guenette, G. Gyuk, D. Hanna, E. Hays, J. Holder, D. Horan, C. M. Hui, T. B. Humensky, A. Imran, P. Kaaret, N. Karlsson, M. Kertzman, D. Kieda, J. Kildea, A. Konopelko, H. Krawczynski, F. Krennrich, M. J. Lang, S. LeBohec, G. Maier, A. McCann, M. McCutcheon, J. Millis, P. Moriarty, R. Mukherjee, T. Nagai, R. A. Ong, A. N. Otte, D. Pandel, J. S. Perkins, D. Petry, M. Pohl, et al. (26 additional authors not shown)

The high-frequency-peaked BL-Lacertae object 1ES 0806+524, at redshift z=0.138, was observed in the very-high-energy (VHE) gamma-ray regime by VERITAS between November 2006 and April 2008. These data encompass the two-, and three-telescope commissioning phases, as well as observations with the full four-telescope array.  1ES 0806+524 is detected with a statistical significance of 6.3 standard deviations from 245 excess events. Little or no measurable variability on monthly time scales is found. The photon spectrum for the period November 2007 to April 2008 can be characterised by a power law with photon index 3.6 ± 1.0stat ± 0.3sys between ~300 GeV and ~700 GeV. The integral ux above 300 GeV is (2.2 ± 0.5stat ± 0.4sys) x 10^-12 cm-2 s-1 which corresponds to
1.8% of the Crab Nebula flux. Non-contemporaneous multiwavelength observations are combined with the VHE data to produce a broadband spectral energy distribution that can be reasonably described using a synchrotron-self-Compton model.

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