由于不透明度的变化,发光的蓝色变星爆发
Yan-Fei Jiang1, Matteo Cantiello2,3, Lars Bildsten4,5
1Kavli Institute for Theoretical Physics, University of California, Santa Barbara, CA, USA. yanfei@kitp.ucsb.edu.
Nature
|September 28, 2018
概括
大量发光的蓝色变量恒星因不透明而发生爆发,如3D模拟所示. 这些模拟还预测了恒星半径和亮度的短期变化.
科学领域:
- 天文学与天体物理学
- 恒星进化
- 计算天体物理学
背景情况:
- 发光的蓝色变量 (LBV) 是巨大的,进化的恒星,以显著的亮度和大小变化而闻名.
- 这些恒星表现出高质量损失率,并经历爆发阶段,降低有效温度.
- 目前的一维模型不足以解释LBV爆发背后的物理机制.
研究的目的:
- 探究导致大质量,辐射占主导地位的恒星爆发和质量损失的物理机制.
- 探索的不透明性和对流在恒星变异性的作用.
- 开发更准确的模型来理解LBV的行为.
主要方法:
- 三维水力学模拟大质量,辐射主导的恒星.
- 用对流来确定恒星外密度和温度.
- 模拟不透明对恒星结构和动态的影响.
主要成果:
- 的不透明度在引发LBV爆发和设置有效温度在9000克尔文左右方面起着至关重要的作用.
- 模拟显示每年10^-7到10^-5太阳质量的周期性质量损失.
- 三维模型揭示了恒星半径的不规则振荡和10-30%的亮度变化.
结论:
- 三维模拟提供了对LBV爆发的新见解,强调了不透明的重要性.
- 交流显著影响恒星的变性,导致可观测的短时间振荡.
- 这些发现需要先进的建模超出一维,球形对称的方法来准确地进行天体物理预测.
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