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Improved Correlation between the Variability and Peak Luminosity of Gamma-Ray Bursts

Li-Xin Li·Bohdan Paczynski
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Abstract

A new procedure for smoothing a gamma-ray burst (GRB) lightcurve and calculating its variability is presented. Applying the procedure to a sample of 25 long GRBs, we have obtained a very tight correlation between the variability and the peak luminosity. The only significant outlier in the sample is GRB 030329. With this outlier excluded, the data scatter is reduced by a factor of \sim 3 compared to that of Guidorzi et al. (2005), measured by the deviation of fit. Possible causes for the outlier are discussed.

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Li-Xin Li, Bohdan Paczynski. 2005-11-09. Improved Correlation between the Variability and Peak Luminosity of Gamma-Ray Bursts. https://doi.org/10.1111/j.1365-2966.2005.09836.x

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