ar X iv : a st ro - p h / 04 05 12 1 v 1 6 M ay 2 00 4 1 THE SAMPLE OF GAMMA - RAY BURSTS OBSERVED WITH SPI - ACS
نویسنده
چکیده
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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