浮动晶体阻止了白矮星的冷却
Antoine Bédard1, Simon Blouin2, Sihao Cheng3
1Department of Physics, University of Warwick, Coventry, UK. antoine.bedard@warwick.ac.uk.
Nature
|March 6, 2024
概括
由于固体液体蒸过程,冷的白矮星可以维持数十亿年的亮度. 这种引力能量释放解释了恒星冷却的异常延迟,并挑战了"死恒星"概念.
科学领域:
- 天文学
- 恒星进化
- 天体物理学
背景情况:
- 白矮星是恒星残留物,经过数十亿年的冷却.
- 一组结的白矮星表现出恒定的亮度, 挑战传统的冷却模型.
- 这种现象表明未知的能量源抑制了冷却.
研究的目的:
- 调查某些白矮星的冷却延迟的能量来源.
- 解释白矮星的观测特性, 具有异常长的恒定亮度阶段.
- 阐明固体液体蒸在白矮星能量释放中的作用.
主要方法:
- 白矮星结过程的理论建模.
- 分析恒星冷却曲线和亮度数据.
- 研究固体液体蒸和引力能量释放的影响.
主要成果:
- 由于浮性晶体的形成, 固体液体蒸释放出大量的重力能量.
- 这一过程有效地阻止了白矮星的冷却, 持续时间与宇宙的年龄相当.
- 该模型解释了在延迟冷却的白矮星群体中观察到的恒定亮度.
结论:
- 蒸引发的引力能量释放是白矮星冷却延迟的主要机制.
- 这些白矮星不是"死去的",
- 这些发现影响了对恒星融合遗留物和恒星群体的约会的理解.
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