arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2006.04601astro-ph.HEastro-ph.EPastro-ph.SR
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FRB 200428:小行星与磁星的碰撞

FRB 200428: an Impact between an Asteroid and a Magnetar

Jin-Jun Geng, Bing Li, Long-Biao Li, Shao-Lin Xiong, Rolf Kuiper, Yong-Feng Huang

摘要:

一个快速射电暴(FRB)最近被发现与银河系磁星SGR 1935+2154的硬X射线暴有关。因此,涉及FRB的磁星的方案非常受欢迎。在这项工作中,我们认为小行星和磁星之间的撞击可以解释这样的探测。根据我们的计算,一颗质量为$10^{20}$ g的小行星在接近磁星时,将在距离$7 \times 10^9$ cm处被破坏。吸积的物质将沿着磁场线从阿尔文半径$\sim 10^7$ cm流动。落在磁星表面后,会形成一个瞬间的吸积柱,在磁层中产生康普顿化X射线爆发和FRB。我们发现,FRB 200428的所有观测特征都可以在这种情况下自洽地解释。我们预测在这个特定的X射线爆发,这可以作为一个独立的观测测试的准周期振荡。

英文摘要:

A fast radio burst (FRB) was recently detected to be associated with a hard X-ray burst from the Galactic magnetar SGR 1935+2154. Scenarios involving magnetars for FRBs are hence highly favored. In this work, we suggest that the impact between an asteroid and a magnetar could explain such a detection. According to our calculations, an asteroid of mass $10^{20}$ g will be disrupted at a distance of $7 \times 10^9$ cm when approaching the magnetar. The accreted material will flow along the magnetic field lines from the Alfvén radius $\sim 10^7$ cm. After falling onto the magnetar's surface, an instant accretion column will be formed, producing a Comptonized X-ray burst and an FRB in the magnetosphere. We show that all the observational features of FRB 200428 could be interpreted self-consistently in this scenario. We predict quasi-periodic oscillations in this specific X-ray burst, which can serve as an independent observational test.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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