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arXiv · 1408.3042

Gamma-Ray Bursts: Temporal Scales and the Bulk Lorentz Factor

E. Sonbas·G. A. MacLachlan·K. S. Dhuga·P. Veres·A. Shenoy·T. N. Ukwatta
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Abstract

For a sample of Swift and Fermi GRBs, we show that the minimum variability timescale and the spectral lag of the prompt emission is related to the bulk Lorentz factor in a complex manner: For small $Γ$'s, the variability timescale exhibits a shallow (plateau) region. For large $Γ$'s, the variability timescale declines steeply as a function of $Γ$ ($δT\proptoΓ^{-4.05\pm0.64}$). Evidence is also presented for an intriguing correlation between the peak times, t$_p$, of the afterglow emission and the prompt emission variability timescale.

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E. Sonbas, G. A. MacLachlan, K. S. Dhuga, P. Veres, A. Shenoy, T. N. Ukwatta. 2015-03-21. Gamma-Ray Bursts: Temporal Scales and the Bulk Lorentz Factor. https://doi.org/10.1088/0004-637x%2F805%2F2%2F86

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