1304.4168 (A. Shenoy et al.)

Curvature Effects in Gamma-Ray Bursts    [PDF]

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

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 for the peak-flux--peak-frequency relation, i.e., the relation between the $\nu$F$_\nu$ flux and the spectral peak, $E_{peak}$ in the decay phase of a GRB pulse, and spectral lags. We present the case of the single-pulse Fermi GRB 110920, as a test for the predictions of the model against observations.

View original: http://arxiv.org/abs/1304.4168