VERITAS OBSERVATIONS OF A VERY HIGH ENERGY gamma-RAY FLARE FROM THE BLAZAR 3C 66A

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2009-03-10

Author

Acciari, V. A.
Aliu, E.
Arlen, T.
Beilicke, M.
Benbow, W.
Boettcher, M.
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.
Daniel, M. K.
Dickherber, R.
Ergin, Tülün
Falcone, A.
Fegan, S. J.
Finley, J. P.
Fortin, P.
Fortson, L.
Furniss, A.
Gall, D.
Gibbs, K.
Gillanders, G. H.
Godambe, S.
Grube, J.
Guenette, R.
Gyuk, G.
Hanna, D.
Hays, E.
Holder, J.
Horan, D.
Hui, C. M.
Humensky, T. B.
Imran, A.
Kaaret, P.
Karlsson, N.
Kertzman, M.
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.
Mukherjee, R.
Nagai, T.
Ong, R. A.
Otte, N.
Pandel, D.
Perkins, J. S.
Petry, D.
Pizlo, F.
Pohl, M.
Quinn, J.
Ragan, K.
Reyes, L. C.
Reynolds, T.
Roache, E.
Rose, H. J.
Schroedter, M.
Sembroski, G. H.
Smith, A. W.
Steele, D.
Swordy, S. P.
Theiling, M.
Toner, J. A.
Varlotta, A.
Vassiliev, V. V.
Wagner, R. G.
Wakely, S. P.
Ward, J. E.
Weekes, T. C.
Weinstein, A.
Williams, D. A.
Wissel, S.
Wood, M.
Zitzer, B.

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The intermediate-frequency peaked BL Lacertae (IBL) object 3C 66A is detected during 2007-2008 in VHE ( very high energy; E > 100 GeV) gamma rays with the VERITAS stereoscopic array of imaging atmospheric Cherenkov telescopes. An excess of 1791 events is detected, corresponding to a significance of 21.2 standard deviations (sigma), in these observations (32.8 hr live time). The observed integral flux above 200 GeV is 6% of the Crab Nebula's flux and shows evidence for variability on the timescale of days. The measured energy spectrum is characterized by a soft power law with photon index Gamma = 4.1 +/- 0.4(stat) +/- 0.6(sys). The radio galaxy 3C 66B is excluded as a possible source of the VHE emission.

Subject Keywords

Space and Planetary Science, Astronomy and Astrophysics

URI

https://hdl.handle.net/11511/40405

Journal

ASTROPHYSICAL JOURNAL LETTERS

DOI

https://doi.org/10.1088/0004-637x/693/2/l104

Collections

Department of Physics, Article

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Citation Formats

V. A. Acciari et al., “VERITAS OBSERVATIONS OF A VERY HIGH ENERGY gamma-RAY FLARE FROM THE BLAZAR 3C 66A,” ASTROPHYSICAL JOURNAL LETTERS, pp. 0–0, 2009, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/40405.