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Temporal and Spectral Characteristics of Short Bursts from the Soft Gamma Repeaters 1806-20 and 1900+14

Ersin Gogus·Chryssa Kouveliotou·Peter M. Woods·Christopher Thompson·Robert C. Duncan·Michael S. Briggs
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Abstract

We study the temporal and coarse spectral properties of 268 bursts from SGR 1806-20 and 679 bursts from SGR 1900+14, all observed with the Rossi X-Ray Timing Explorer/Proportional Counter Array. Hardness ratios and temporal parameters, such as T_90 durations and tau_90 emission times are determined for these bursts. We find a lognormal distribution of burst durations, ranging over more than two orders of magnitude: T_90 ~ 10^-2 to >~ 1 s, with a peak at ~ 0.1 s. The burst light curves tend to be asymmetrical, with more than half of all events showing rise times t_r < 0.3 T_90. We find that there exists a correlation between the duration and fluence of bursts from both sources. We also find a significant anti-correlation between hardness ratio and fluence for SGR 1806-20 bursts and a marginal anti-correlation for SGR 1900+14 events. Finally, we discuss possible physical implications of these results within the framework of the magnetar model.

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Ersin Gogus, Chryssa Kouveliotou, Peter M. Woods, Christopher Thompson, Robert C. Duncan, Michael S. Briggs. 2001-05-07. Temporal and Spectral Characteristics of Short Bursts from the Soft Gamma Repeaters 1806-20 and 1900+14. https://doi.org/10.1086/322463

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