在dSct恒星中,通过高效的外对流来激发类似太阳的振荡
V Antoci1, G Handler, T L Campante
1Institute of Astronomy, University of Vienna, Türkenschanzstrasse 18, A-1180 Vienna, Austria. victoria.antoci@univie.ac.at
Nature
|September 16, 2011
概括
研究人员在Delta Scuti (δSct) 恒星中检测到类似太阳的振荡,证实了两倍于太阳质量的恒星中高效的表面对流. 这一发现支持了恒星脉动和结构的理论模型.
科学领域:
- 恒星天体物理学 恒星天体物理学
- 星星地震学是一门学科.
- 恒星结构和进化过程
背景情况:
- 达尔塔斯库蒂 (δSct) 恒星是不透明驱动的脉冲星,质量是太阳 (M) 的1.52.5倍.
- 它们的脉冲是由电离驱动的,类似于太阳声学模式,但理论模型预测了dSct恒星的有限对流包裹.
- 以前的观测没有证实存在显著的对流膜,质疑现有的模型.
研究的目的:
- 为了研究 δSct 恒星中表面对流的存在和效率.
- 测试理论预测的对流膜范围在质量约为2M的恒星.
- 为了寻找 δSct 恒星中的类似太阳振荡,作为对流的指标.
主要方法:
- 使用开普勒任务数据检测类似太阳的振荡.
- 对脉冲光谱的分析以确定共振声学模式.
- 观察到的振荡与恒星模型的比较.
主要成果:
- 在 δSct 恒星 HD187547.7.中检测出类似太阳振荡的明确信号.
- 观测到的振荡意味着一颗大约两倍于太阳质量的恒星的高效表面对流.
- 这一发现与以前未经证实的理论模型的预测一致.
结论:
- 表面对流在dSct恒星中比以前基于观测证据所认为的更有效.
- 检测到类似太阳的振荡验证了理论模型,这些模型预测了这些恒星中显著的对流罩.
- 这项研究推动了我们对中等质量恒星的恒星结构和脉冲机制的理解.
相关概念视频
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