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Properties of Gamma-Ray Burst Classes

Jon Hakkila·David J. Haglin·Richard J. Roiger·Robert S. Mallozzi·Geoffrey N. Pendleton·Charles A. Meegan
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Abstract

The three gamma-ray burst (GRB) classes identified by statistical clustering analysis (Mukherjee et al. 1998) are examined using the pattern recognition algorithm C4.5 (Quinlan 1986). Although the statistical existence of Class 3 (intermediate duration, intermediate fluence, soft) is supported, the properties of this class do not need to arise from a distinct source population. Class 3 properties can easily be produced from Class 1 (long, high fluence, intermediate hardness) by a combination of measurement error, hardness/intensity correlation, and a newly-identified BATSE bias (the fluence duration bias). Class 2 (short, low fluence, hard) does not appear to be related to Class 1.

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Jon Hakkila, David J. Haglin, Richard J. Roiger, Robert S. Mallozzi, Geoffrey N. Pendleton, Charles A. Meegan. 2000-01-19. Properties of Gamma-Ray Burst Classes. https://doi.org/10.1063/1.1361502

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