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arXiv · 1410.5367

Constraints on Very High Energy Emission from GRB 130427A

Abstract

Prompt emission from the very fluent and nearby (z=0.34) gamma-ray burst GRB 130427A was detected by several orbiting telescopes and by ground-based, wide-field-of-view optical transient monitors. Apart from the intensity and proximity of this GRB, it is exceptional due to the extremely long-lived high-energy (100 MeV to 100 GeV) gamma-ray emission, which was detected by the Large Area Telescope on the Fermi Gamma-ray Space Telescope for ~70 ks after the initial burst. The persistent, hard-spectrum, high-energy emission suggests that the highest-energy gamma rays may have been produced via synchrotron self-Compton processes though there is also evidence that the high-energy emission may instead be an extension of the synchrotron spectrum. VERITAS, a ground-based imaging atmospheric Cherenkov telescope array, began follow-up observations of GRB 130427A ~71 ks (~20 hr) after the onset of the burst. The GRB was not detected with VERITAS; however, the high elevation of the observations, coupled with the low redshift of the GRB, make VERITAS a very sensitive probe of the emission from GRB 130427A for E > 100 GeV. The non-detection and consequent upper limit derived place constraints on the synchrotron self-Compton model of high-energy gamma-ray emission from this burst.

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E. Aliu, T. Aune, A. Barnacka, M. Beilicke, W. Benbow, K. Berger, J. Biteau, J. H. Buckley, V. Bugaev, K. Byrum, J. V Cardenzana, M. Cerruti, X. Chen, L. Ciupik, V. Connaughton, W. Cui, H. J. Dickinson, J. D. Eisch, M. Errando, A. Falcone, S. Federici, Q. Feng, J. P. Finley, H. Fleischhack, P. Fortin, L. Fortson, A. Furniss, N. Galante, G. H. Gillanders, S. Griffin, S. T. Griffiths, J. Grube, G. Gyuk, N. Håkansson, D. Hanna, J. Holder, G. Hughes, T. B. Humensky, C. A. Johnson, P. Kaaret, P. Kar, M. Kertzman, Y. Khassen, D. Kieda, H. Krawczynski, F. Krennrich, M. J. Lang, A. S. Madhavan, G. Maier, S. McArthur, A. McCann, K. Meagher, J. Millis, P. Moriarty, R. Mukherjee, D. Nieto, A. O'Faoláin de Bhróithe, R. A. Ong, A. N. Otte, N. Park, M. Pohl, A. Popkow, H. Prokoph, E. Pueschel, J. Quinn, K. Ragan, J. Rajotte, L. C. Reyes, P. T. Reynolds, G. T. Richards, E. Roache, G. H. Sembroski, K. Shahinyan, A. W. Smith, D. Staszak, I. Telezhinsky, J. V. Tucci, J. Tyler, A. Varlotta, V. V. Vassiliev, S. Vincent, S. P. Wakely, O. M. Weiner, A. Weinstein, R. Welsing, A. Wilhelm, D. A. Williams, B. Zitzer, J. E. McEnery, J. S. Perkins, P. Veres, S. Zhu. 2014-10-20. Constraints on Very High Energy Emission from GRB 130427A. https://doi.org/10.1088/2041-8205%2F795%2F1%2Fl3

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