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arXiv · 1511.08925

Analysis of the observed and intrinsic durations of $Swift$/BAT gamma-ray bursts

Mariusz Tarnopolski
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Abstract

The duration distribution of 947 GRBs observed by $Swift$/BAT, as well as its subsample of 347 events with measured redshift, allowing to examine the durations in both the observer and rest frames, are examined. Using a maximum log-likelihood method, mixtures of two and three standard Gaussians are fitted to each sample, and the adequate model is chosen based on the value of the difference in the log-likelihoods, Akaike information criterion and Bayesian information criterion. It is found that a two-Gaussian is a better description than a three-Gaussian, and that the presumed intermediate-duration class is unlikely to be present in the $Swift$ duration data.

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Mariusz Tarnopolski. 2016-01-14. Analysis of the observed and intrinsic durations of $Swift$/BAT gamma-ray bursts. https://doi.org/10.1016/j.newast.2015.12.006

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