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arXiv · 1405.4867

An Analysis of Chandra Deep Follow-up GRBs: Implications for Off-Axis Jets

Bin-Bin Zhang·Hendrik van Eerten·David N. Burrows·Geoffrey Scott Ryan·Philip A. Evans·Judith L. Racusin·Eleonora Troja·Andrew MacFadyen
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Abstract

We present a sample of 27 GRBs with detailed Swift light curves supplemented by late time Chandra observations. To answer the missing jet-break problem in general, we develop a numerical simulation based model which can be directly fit to the data using Monte Carlo methods. Our numerical model takes into account all the factors that can shape a jet-break: (i) lateral expansion (ii) edge effects and (iii) off-axis effects. Our results provide improved fits to the light curves and constraints on physical parameters. More importantly, our results suggest that off-axis effects are important and must be included in interpretations of GRB jet breaks.

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Bin-Bin Zhang, Hendrik van Eerten, David N. Burrows, Geoffrey Scott Ryan, Philip A. Evans, Judith L. Racusin, Eleonora Troja, Andrew MacFadyen. 2015-04-05. An Analysis of Chandra Deep Follow-up GRBs: Implications for Off-Axis Jets. https://doi.org/10.1088/0004-637x%2F806%2F1%2F15

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