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The 1st INTEGRAL SPI-ACS Gamma-Ray Burst Catalogue

A. Rau·A. v. Kienlin·K. Hurley·G. G. Lichti
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Abstract

We present the sample of gamma-ray bursts detected with the anti-coincidence shield ACS of the spectrometer SPI on-board INTEGRAL for the first 26.5 months of mission operation (up to Jan 2005). SPI-ACS works as a nearly omnidirectional gamma-ray burst detector above ~80 keV but lacks spatial and spectral information. In this catalogue, the properties derived from the 50 ms light curves (e.g., T90, Cmax, Cint, variability, V/Vmax) are given for each candidate burst in the sample. A strong excess of very short events with durations <0.25 s is found. This population is shown to be significantly different from the short- and long-duration burst sample by means of the intensity distribution and V/Vmax test and is certainly connected with cosmic ray hits in the detector. A rate of 0.3 true gamma-ray bursts per day is observed.

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A. Rau, A. v. Kienlin, K. Hurley, G. G. Lichti. 2005-04-15. The 1st INTEGRAL SPI-ACS Gamma-Ray Burst Catalogue. https://doi.org/10.1051/0004-6361%3A20053159

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