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Published on: February 12, 2013
富含卢比的非对称巨型分支恒星
D A García-Hernández1, P García-Lario, B Plez
1ISO Data Centre, European Space Astronomy Centre, Research and Scientific Support Department, European Space Agency, Villafranca del Castillo, Apdo. 50727, E-28080 Madrid, Spain. agarcia@astro.as.utexas.edu
概括
天文学家发现了富含卢比的恒星,提供了证据表明 (22) Ne ((alpha,n) ((25) Mg反应是非对称巨分支 (AGB) 恒星中的主要中子源. 这一发现影响了我们对恒星进化和早期太阳系状况的理解.
科学领域:
- 恒星核合成 恒星核合成
- 天文学 天文学
- 天体物理学 天体物理学
背景情况:
- 在非对称巨分支 (AGB) 恒星中富含中子元素的起源仍然是一个长期存在的难题.
- 确定主要中子源对于理解恒星进化和银河系化学丰富至关重要.
研究的目的:
- 为中质量AGB恒星中占主导地位的中子源提供观测证据.
- 研究长寿命放射性同位素鲁比-87 ((87) Rb) 的核合成.
主要方法:
- 在我们的银河系中观测和分析中等质量 (4-8太阳质量) AGB恒星.
- 识别表现出过多的恒星.
主要成果:
- 发现富含卢比的AGB恒星,符合40年前的理论预测.
- 直接的观测证据支持这些恒星中作为主要中子源的 (22) Ne ((alpha,n) ((25) Mg反应.
结论:
- 证实了 (22) Ne ((alpha,n) ((25) Mg反应是中等质量AGB恒星中占主导地位的中子源.
- 这些发现挑战了目前晚期恒星进化的模型,并表明了早期太阳星云中的可变Rb/Sr环境.
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