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arXiv · 1403.6739

To understand the X-ray spectrum of anomalous X-ray pulsars and soft gamma-ray repeaters

Yan-Jun Guo·Shi Dai·Zhao-Sheng Li·Yuan Liu·Hao Tong·Ren-Xin Xu
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Abstract

Hard X-rays above 10 keV are detected from several anomalous X-ray pulsars (AXPs) and soft gamma-ray repeaters (SGRs), and different models have been proposed to explain the physical origin within the frame of either magnetar model or fallback disk system. Using data from $\it Suzaku$ and INTEGRAL, we study the soft and hard X-ray spectra of four AXPs/SGRs, 1RXS J170849-400910, 1E 1547.0-5408, SGR 1806-20 and SGR 0501+4516. It is found that the spectra could be well reproduced by bulk-motion Comptonization (BMC) process as was first suggested by Tr$\"u$mper et al., showing that the accretion scenario could be compatible with X-ray emission of AXPs/SGRs. HXMT simulations for BMC model show that the spectra would have discrepancies from power-law, especially the cutoff at $\sim$ 200 keV. Thus future observations are promising to distinguish different models for the hard tail and may help us understand the nature of AXPs/SGRs.

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Yan-Jun Guo, Shi Dai, Zhao-Sheng Li, Yuan Liu, Hao Tong, Ren-Xin Xu. 2014-03-26. To understand the X-ray spectrum of anomalous X-ray pulsars and soft gamma-ray repeaters. https://doi.org/10.1088/1674-4527/15/4/006

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