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'On the difference between the short and long gamma-ray bursts'

L. G. Balazs·Z. Bagoly·I. Horvath·A. Meszaros·P. Meszaros
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Abstract

We argue that the distributions of both the intrinsic fluence and the intrinsic duration of the gamma-ray emission in gamma-ray bursts from the BATSE sample are well represented by log-normal distributions, in which the intrinsic dispersion is much larger than the cosmological time dilatation and redshift effects. We perform separate bivariate log-normal distribution fits to the BATSE short and long burst samples. The bivariate log-normal behaviour results in an ellipsoidal distribution, whose major axis determines an overall statistical relation between the fluence and the duration. We show that this fit provides evidence for a power-law dependence between the fluence and the duration, with a statistically significant different index for the long and short groups. We discuss possible biases, which might affect this result, and argue that the effect is probably real. This may provide a potentially useful constraint for models of long and short bursts.

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L. G. Balazs, Z. Bagoly, I. Horvath, A. Meszaros, P. Meszaros. 2003-01-14. 'On the difference between the short and long gamma-ray bursts'. https://doi.org/10.1051/0004-6361%3A20021863

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