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arXiv · 1304.4168

Probing Curvature Effects in the Fermi GRB 110920

A. Shenoy·E. Sonbas·C. Dermer·L. C. Maximon·K. S. Dhuga·P. N. Bhat·J. Hakkila·W. C. Parke·G. A. Maclachlan·T. N. Ukwatta
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Abstract

Curvature effects in Gamma-ray bursts (GRBs) have long been a source of considerable interest. In a collimated relativistic GRB jet, photons that are off-axis relative to the observer arrive at later times than on-axis photons and are also expected to be spectrally softer. In this work, we invoke a relatively simple kinematic two-shell collision model for a uniform jet profile and compare its predictions to GRB prompt-emission data for observations that have been attributed to curvature effects such as the peak-flux--peak-frequency relation, i.e., the relation between the $\nu$F$_\nu$ flux and the spectral peak, E$_{pk}$ in the decay phase of a GRB pulse, and spectral lags. In addition, we explore the behavior of pulse widths with energy. We present the case of the single-pulse Fermi GRB 110920, as a test for the predictions of the model against observations.

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A. Shenoy, E. Sonbas, C. Dermer, L. C. Maximon, K. S. Dhuga, P. N. Bhat, J. Hakkila, W. C. Parke, G. A. Maclachlan, T. N. Ukwatta. 2013-04-15. Probing Curvature Effects in the Fermi GRB 110920. https://doi.org/10.1088/0004-637x%2F778%2F1%2F3

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