C. Martínez-Sebastián, S. Simón-Díaz, H. Jin, Z. Keszthelyi, G. Holgado, N. Langer, J. Puls
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引用次数: 0
Abstract
There is increasing evidence that single-star evolutionary models are unable to reproduce all of the observational properties of massive stars. Binary interaction has emerged as a key factor in the evolution of a significant fraction of massive stars. In this study, we investigate the helium (YHe) and nitrogen (ϵN) surface abundances in a comprehensive sample of 180 Galactic O-type stars with projected rotational velocities of ≤150 km s−1. We found a subsample (∼20% of the total, and ∼80% of the stars with YHe ≥ 0.12) with a YHe and ϵN combined pattern that is unexplainable by single-star evolution. We argue that the stars with anomalous surface abundance patterns are binary interaction products.
越来越多的证据表明,单星演化模型无法再现大质量恒星的所有观测特性。双星相互作用已经成为很大一部分大质量恒星演化的关键因素。在这项研究中,我们研究了180颗银河系o型恒星的氦(YHe)和氮(ϵN)表面丰度,这些恒星的预计转速≤150 km s−1。我们发现了一个子样本(约占总数的20%,约占YHe≥0.12的恒星的80%),其YHe和ϵN组合模式是单星演化无法解释的。我们认为具有异常表面丰度模式的恒星是双星相互作用的产物。
期刊介绍:
Astronomy & Astrophysics is an international Journal that publishes papers on all aspects of astronomy and astrophysics (theoretical, observational, and instrumental) independently of the techniques used to obtain the results.