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On the nature of soft Gamma-ray repeaters

Bing Zhang
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Abstract

Soft gamma-ray repeaters (SGRs) and Anomalous X-ray pulsars (AXPs) are generally accepted to be magnetars. Recently, Zhang, Xu & Qiao (2000, ApJ, 545, L127) proposed an alternative viewpoint about the nature of the SGRs (and AXPs). In this picture, SGR bursts are attributed to the impacts of some comet-like objects with the central bare strange star. Here I briefly review this model, and confront it with the detailed observations of SGRs/AXPs. A comparison to the magnetar model is also presented. Some theoretical issues concerning the nature of the SGRs (and AXPs) are discussed.

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Bing Zhang. 2001-02-06. On the nature of soft Gamma-ray repeaters. https://arxiv.org/abs/astro-ph/0102098

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