一个相对论类型的Ibc超新星,没有检测到的马射线爆发
A M Soderberg1, S Chakraborti, G Pignata
1Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS-51, Cambridge, Massachusetts 02138, USA. asoderberg@cfa.harvard.edu
Nature
|January 30, 2010
概括
科学家们发现了超新星SN 2009bb的发光无线电辐射,表明来自中央发动机的强大外流. 这表明,通过寻找超新星中的相对论外流来寻找隐藏的马射线爆发 (GRBs) 的新方法.
科学领域:
- 天体物理学 天体物理学
- 宇宙爆炸,宇宙爆炸.
- 超新星和马射线爆炸
背景情况:
- 长时间的马射线爆发 (GRB) 与大质量恒星的爆炸性死亡有关,形成了一种罕见的Ibc型超新星子类.
- 这些事件的特点是来自中央引擎 (黑洞或中子星) 的相对论外流,被观察为马射线脉冲和无线电余照.
- 由于仪器灵敏度限制或辐射远离地球,许多GRB可能无法被检测到.
研究的目的:
- 通过对具有相对论外流的超新星的无线电搜索来研究检测以前未被发现的GRB的可能性.
- 为了识别超新星表现出超出玛射线检测范围的中央发动机活动特征.
主要方法:
- 进行了对Ibc型超新星的无线电调查.
- 来自SN 2009bb的发光射线辐射的分析,以推断相对论外流的存在.
- 将发现与关于GRB频率和超新星群体的现有数据进行比较.
主要成果:
- 从Ibc型超新星SN 2009bb中检测到发光无线电辐射,表明由中央发动机驱动的大量相对论外流.
- 该研究估计,大约1%的Ibc型超新星拥有中央发动机,这与独立的GRB速率估计相一致.
- 第二个轻微相对论超新星也被独立识别出来.
结论:
- 无线电观测可以通过检测超新星中的相对论外流来揭示隐藏的马射线爆发 (GRB) 群体.
- 超新星SN 2009bb在以前未经分类的事件中提供了中央发动机活动的证据.
- 超新星中中央引擎的流行率很低,但与观测到的GRB速率一致,这表明存在大量未被检测到的GRB群体.
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