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arXiv · 1403.6244

The short bursts in SGR 1806-20, 1E 1048-5937 and SGR 0501+4516

Zhijie Qu·Zhaosheng Li·Yupeng Chen·Shi Dai·Long Ji·Renxin Xu·Shu Zhang
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Abstract

We analyzed temporal and spectral properties, focusing on the short bursts, for three anomalous X-ray pulsars (AXPs) and soft gamma repeaters (SGRs), including SGR 1806-20, 1E 1048-5937 and SGR 0501+4516. Using the data from XMM-Newton, we located the short bursts by Bayesian blocks algorithm. The short bursts' duration distributions for three sources were fitted by two lognormal functions. The spectra of shorter bursts ($< 0.2~\rm s$) and longer bursts ($\geq 0.2~\rm s$) can be well fitted in two blackbody components model or optically thin thermal bremsstrahlung model for SGR 0501+4516. We also found that there is a positive correlation between the burst luminosity and the persistent luminosity with a power law index $γ= 1.23 \pm 0.18 $. The energy ratio of this persistent emission to the time averaged short bursts is in the range of $10 - 10^3$, being comparable to the case in Type I X-ray burst.

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Zhijie Qu, Zhaosheng Li, Yupeng Chen, Shi Dai, Long Ji, Renxin Xu, Shu Zhang. 2015-01-14. The short bursts in SGR 1806-20, 1E 1048-5937 and SGR 0501+4516. https://doi.org/10.1086/680484

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