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arXiv · 1206.4080

Multiwavelength observations of the AGN 1ES 0414+009 with VERITAS, Fermi-LAT, Swift-XRT, and MDM

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 January 2008 and February 2011, resulting in 56.2 hours 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 * 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 an 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 * 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.

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E. Aliu, S. Archambault, T. Arlen, T. Aune, M. Beilicke, W. Benbow, M. Bottcher, A. Bouvier, V. Bugaev, A. Cannon, A. Cesarini, L. Ciupik, E. Collins-Hughes, M. P. Connolly, W. Cui, R. Dickherber, J. Dumm, M. Errando, A. Falcone, S. Federici, Q. Feng, J. P. Finley, G. Finnegan, L. Fortson, A. Furniss, N. Galante, D. Gall, S. Godambe, S. Griffin, J. Grube, G. Gyuk, D. Hanna, H. Huan, G. Hughes, C. M. Hui, A. Imran, O. Jameil, P. Kaaret, N. Karlsson, M. Kertzman, J. Kerr, Y. Khassen, D. Kieda, H. Krawczynski, F. Krennrich, M. J. Lang, K. Lee, A. S. Madhavan, P. Majumdar, S. McArthur, A. McCann, P. Moriarty, R. Mukherjee, T. Nelson, A. O'Faolain de Bhroithe, R. A. Ong, M. Orr, A. N. Otte, N. Park, J. S. Perkins, A. Pichel, M. Pohl, J. Quinn, K. Ragan, P. T. Reynolds, E. Roache, J. Ruppel, D. B. Saxon, M. Schroedter, G. H. Sembroski, G. D. Senturk, A. W. Smith, D. Staszak, M. Stroh, I. Telezhinsky, G. Tesic, M. Theiling, S. Thibadeau, K. Tsurusaki, A. Varlotta, V. V. Vassiliev, M. Vivier, S. P. Wakely, J. E. Ward, A. Weinstein, R. Welsing, D. A. Williams, B. Zitzer. 2012-06-20. Multiwavelength observations of the AGN 1ES 0414+009 with VERITAS, Fermi-LAT, Swift-XRT, and MDM. https://doi.org/10.1088/0004-637x%2F755%2F2%2F118

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