缓慢色的超光超新星不是对不稳定性爆炸
M Nicholl1, S J Smartt, A Jerkstrand
1Astrophysics Research Centre, School of Mathematics and Physics, Queen's University Belfast, Belfast BT7 1NN, UK. mnicholl03@qub.ac.uk
Nature
|October 18, 2013
概括
两个新的超亮超新星挑战了对不稳定模型. 观测表明磁器驱动的爆炸可能解释这些和类似的宇宙事件,这表明对不稳定的超新星是罕见的.
科学领域:
- 天文学和天体物理学
- 太空爆炸 太空爆炸
- 恒星进化 恒星进化
背景情况:
- 超亮超新星 (SLSNe) 是在遥远的星系中观察到的强大的恒星爆炸.
- 一些SLSNe类似于理论上的"对不稳定性"超新星,起源于早期宇宙中的大质量恒星.
- 超新星2007bi是一个潜在的对不稳定事件,其特征目前正在重新评估.
研究的目的:
- 为了研究两个具有异常观测性质的SLSNe的性质.
- 确定这些SLSNe是否与对不稳定模型或替代爆炸机制相一致.
- 重新评估对不稳定的超新星的特征和流行情况.
主要方法:
- 来自两个SLSNe的光曲线和光谱的观察和分析.
- 观察数据与理论模型的比较,包括对不稳定性和磁器驱动的爆炸.
- 评估对对不稳定性超新星的速度的影响.
主要成果:
- 两个SLSNe表现出快速上升时间和蓝色,与对不稳定模型不一致.
- 晚期光曲线和光谱与超新星2007bi有相似之处,质疑其分类.
- 建模表明,磁性能量喷射物 (10-16太阳质量) 可以解释观察到的现象.
- 附近对不稳定事件的发生率似乎非常低.
结论:
- 观察到的SLSNe不太可能是对不稳定事件.
- 磁器驱动的爆炸为这些SLSNe提供了一个合理的替代机制.
- 这些发现表明,对不稳定的超新星可能比以前认为的更罕见.
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