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在最终崩之前, 一个巨大的白矮人合并产物
Vasilii V Gvaramadze1,2,3, Götz Gräfener4, Norbert Langer5,6
1Sternberg Astronomical Institute, Lomonosov Moscow State University, Moscow, Russia. vgvaram@mx.iki.rssi.ru.
Nature
|May 22, 2019
概括
我们观察到一颗热恒星和星云, 这种合并避免了超新星,创造了一个独特的,高度磁化的恒星,并提供了恒星合并中磁场生成的证据.
科学领域:
- 天体物理学
- 恒星进化
- 紧型物体
背景情况:
- 引力波可以导致像中子星和白矮星这样的紧物体合并.
- 合并的白矮星可以超过Chandrasekhar极限,可能导致Ia型超新星或中子星的形成.
- 后一种情况预测一个没有/的星云和一个热的,快速旋转的,磁化的恒星.
研究的目的:
- 报告一个独特的恒星系统的观测.
- 在星云中心研究一颗热恒星的性质.
- 确定这个系统是不是由白矮星的合并形成的,
主要方法:
- 观测天文学,包括中红外成像.
- 恒星发射线的光谱分析.
- 恒星大气和风的模型.
主要成果:
- 观测到一个热恒星 (约. 在一个圆形的中红外星云中.
- 排放线的宽度表明流出速度很高 (16,000公里/秒),表明旋转速度快且磁场强.
- 在恒星和星云中缺少和.
结论:
- 观测到的恒星和星云很可能是两颗巨大的白矮星合并后的产物.
- 这种合并避免了Ia型超新星,形成了崩后的物体.
- 这些发现提供了白矮星合并期间产生磁场的证据.
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