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The Sample of Gamma-ray Bursts Observed With SPI-ACS

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

The SPI anticoincidence shield consists of 91 BGO crystals and is operated as a nearly omnidirectional gamma-ray burst detector above ~75 keV. Since the start of the mission 269 gamma-ray burst candidates have been detected. 110 bursts have been confirmed with the instruments included in the 3rd Interplanetary Network. Here we present a preliminary statistical analysis of the SPI-ACS sample of gamma-ray bursts and gamma-ray burst candidates; in particular we discuss the duration distribution of the bursts. A prominent population of short burst candidates (duration <200ms) is found which is discovered to be strongly contaminated by cosmic-ray nuclei interacting in the detectors.

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A. Rau, A. von Kienlin, K. Hurley, G. G. Lichti. 2004-05-06. The Sample of Gamma-ray Bursts Observed With SPI-ACS. https://doi.org/10.1393/ncc%2Fi2005-10051-3

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