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浏览/检索结果: 共1条，第1-1条 帮助 已选(0)清除 条数/页：5101520253035404550556065707580859095100   排序方式：请选择发表日期升序发表日期降序提交时间升序提交时间降序题名升序题名降序作者升序作者降序 Detection of two bright radio bursts from magnetar SGR 1935 + 2154 期刊论文 Nature Astronomy, 2021, 卷号: 5, 页码: 414 作者:  Kirsten, F.;  Snelders, M. P.;  Jenkins, M.;  Nimmo, K.;  van den Eijnden, J. 收藏  |  浏览/下载：41/0  |  提交时间：2021/11/18 Astrophysics - High Energy Astrophysical Phenomena  Abstract: Fast radio bursts are millisecond-duration, bright radio signals (fluence 0.1-100 Jy ms) emitted from extragalactic sources of unknown physical origin. The recent CHIME/FRB and STARE2 detection of an extremely bright (fluence ~MJy ms) radio burst from the Galactic magnetar SGR 1935+2154 supports the hypothesis that (at least some) fast radio bursts are emitted by magnetars at cosmological distances. In follow-up observations totalling 522.7 h on source, we detect two bright radio bursts with fluences of 112 ± 22 Jy ms and 24 ± 5 Jy ms, respectively. Both bursts appear to be affected by interstellar scattering and we measure significant linear and circular polarization for the fainter burst. The bursts are separated in time by ~1.4 s, suggesting a non-Poissonian, clustered emission processsimilar to those seen in some repeating fast radio bursts. Together with the burst reported by CHIME/FRB and STARE2, as well as a much fainter burst seen by FAST (fluence 60 mJy ms), our observations demonstrate that SGR 1935+2154 can produce bursts with apparent energies spanning roughly seven orders of magnitude, and that the burst rate is comparable across this range. This raises the question of whether these four bursts arise from similar physical processes, and whether the fast radio burst population distribution extends to very low energies (~1030 erg, isotropic equivalent).