一颗WC/WO恒星在一个膨胀的碳-氧-星中爆炸
A Gal-Yam1, R Bruch2, S Schulze2,3
1Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel. avishay.gal-yam@weizmann.ac.il.
Nature
|January 13, 2022
概括
巨大的沃尔夫-雷耶恒星,特别是耗尽的WC/WO类型,可能是快速演变的短暂恒星的祖先. 对SN 2019hgp的观测表明这些恒星可能会爆炸,这挑战了以前关于直接黑洞崩的理论.
科学领域:
- 天体物理学
- 恒星进化
- 暂时的天文学
背景情况:
- 巨大的恒星及其紧的残余物 (黑洞,中子星) 的最终命运仍然是一个悬而未决的问题.
- 巨大的恒星失去了包裹, 演变为具有强大的风的狼雷特恒星.
- 耗尽的WC/WO Wolf-Rayet恒星被怀疑会直接崩成黑洞,避免可见的超新星.
研究的目的:
- 调查快速演变的短暂SN 2019hgp的原始物.
- 为了确定大质量狼-雷耶恒星是否能产生可观测的超新星爆炸.
- 了解狼雷耶恒星与缺乏/的超新星之间的联系.
主要方法:
- 观测天文学利用SN 2019hgp爆炸后不久的光谱.
- 对排放和吸收线特征进行分析,以确定喷射物的组成和膨胀速度.
- 与恒星进化和超新星的理论模型对观察过渡性质的比较.
主要成果:
- SN 2019hgp表现出短暂的上升时间和快速下降,这是快速演变的特征.
- 光谱检测发现了碳,氧和的排放线,以及高速吸收特征 (> 1,500 km/s).
- 这些发现与来自巨型WC/WO恒星的爆炸一致.
结论:
- 巨大的沃尔夫-雷耶恒星,特别是WC/WO类型的恒星,可能是可观测的超新星爆炸的原始体.
- 观测到的SN 2019hgp的特性支持了这些恒星可能导致快速演变的过渡体的假设.
- 这挑战了大多数这样的恒星直接经历黑洞崩而没有明显的爆炸的观念.
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