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arXiv · 1111.2922

Unusual Central Engine Activity in the Double Burst GRB 110709B

Bin-Bin Zhang·David Burrows·Bing Zhang·Peter Meszaros·Xiang-Yu Wang·Giulia Stratta·Valerio D'Elia·Dmitry Frederiks·Sergey Golenetskii·Jay R. Cummings·Jay P. Norris·Abraham Falcone·Scott D. Barthelmy·Neil Gehrels
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Abstract

The double burst, GRB 110709B, triggered Swift/BAT twice at 21:32:39 UT and 21:43:45 UT, respectively, on 9 July 2011. This is the first time we observed a GRB with two BAT triggers. In this paper, we present simultaneous Swift and Konus-WIND observations of this unusual GRB and its afterglow. If the two events originated from the same physical progenitor, their different time-dependent spectral evolution suggests they must belong to different episodes of the central engine, which may be a magnetar-to-BH accretion system.

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Bin-Bin Zhang, David Burrows, Bing Zhang, Peter Meszaros, Xiang-Yu Wang, Giulia Stratta, Valerio D'Elia, Dmitry Frederiks, Sergey Golenetskii, Jay R. Cummings, Jay P. Norris, Abraham Falcone, Scott D. Barthelmy, Neil Gehrels. 2011-11-12. Unusual Central Engine Activity in the Double Burst GRB 110709B. https://doi.org/10.1088/0004-637x/748/2/132

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