能量爆发导致一颗巨大的恒星独特的富含的爆炸
Iair Arcavi1,2,3, D Andrew Howell1,3, Daniel Kasen4,5,6
1Las Cumbres Observatory, Goleta, California 93117, USA.
Nature
|November 10, 2017
概括
一个奇特的超新星,iPTF14hls, 这种宇宙事件表明大质量恒星中异常的质量喷射机制,
科学领域:
- 天文学
- 天体物理学
- 恒星进化
背景情况:
- 超新星通常被理解为恒星的最终爆炸.
- 观测到的超新星呈现下降的光谱线速度和单一的光曲线峰值或平原.
- 富含的超新星通常具有持续约100天的特征光线曲线.
研究的目的:
- 报告和分析超新星iPTF14hls的独特观测特性.
- 调查iPTF14hls对恒星爆炸模型的影响.
主要方法:
- 对iPTF14hls进行光谱分析.
- 在长时间内对 iPTF14hls 的光曲线进行光度监测.
- 与已知超新星类型和理论模型对比 iPTF14hls 的特性.
主要成果:
- iPTF14hls具有至少五个峰值的复杂光线曲线,持续超过600天.
- 光谱吸收线显示最小的速度下降,线形成区域明显大于预期.
- 在1954年可能有历史上的先例.
结论:
- iPTF14hls具有前所未有的超新星特征,与已知的超新星类型有显著差异.
- 观察到的现象挑战了现有的模型,包括脉冲对的不稳定性,特别是关于的存在和能量.
- 对于大质量恒星的强烈质量喷射, 可能需要一种新的机制来解释像iPTF14hls这样的事件.
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