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A 3rd Class of Gamma Ray Bursts?

I. Horvath
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Abstract

Two classes of Gamma Ray Bursts have been identified so far, characterized by T_90 durations shorter and longer than approximately 2 seconds. We show here that the BATSE 3B data allow a good fit with three Gaussian distributions in log T_90. The chi^2 statistic indicates a 40 % probability for two Gaussians, whereas the three-Gaussian fit probability is 98 %. Using another statistical method, it is argued that the probability that the third class is a random fluctuation is less than 0.02 %.

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I. Horvath. 1998-05-17. A 3rd Class of Gamma Ray Bursts?. https://doi.org/10.1086/306416

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