论文标题
使用观察到的表面条件约束的Betelgeuse的恒星模型
Stellar models of Betelgeuse constrained using observed surface conditions
论文作者
论文摘要
我们使用HR图和表面丰度作为观察限制来研究Betelgeuse的出色模型。先前关于槟榔的研究尚未系统地研究表面丰度，但我们认为它们可以受到影响，因此可以用作各种参数的观察性约束，例如初始质量，旋转和过冲方案。我们研究了具有不同初始质量的恒星模型，它们会超越主序列，并详细检查红色超级巨人（RSG）特性。对于每个质量，我们将初始旋转最多改变为$ \ sim $ 300 $ km \：s^{ - 1} $，并测试两个不同的过冲参数。总体而言，可接受的初始质量范围是12至25 $ m_ \ odot $，但仅对于非旋转模型，该范围降至15至24 $ m_ \ odot $。同样对于旋转模型，我们发现$ v/v _ {\ rm k} = 0.3 $是初始旋转的上限，因为更快的旋转模型无法适合Betelgeuse作为RSG的表面丰度。此外，我们报告了当前进化阶段，核心氦燃烧或核心碳燃烧及其他阶段的两种可能性。我们发现某些17 $ m_ \ odot $型号可以适合两个阶段。最后，我们讨论了结果在合并情景的背景下的含义，该方案被认为是达到观察到的betelgeuse表面速度的一种机制。
We study stellar models for Betelgeuse using the HR diagram and surface abundances as observational constraints. Previous studies on Betelgeuse have not systematically investigated the surface abundances, but we believe they can be impacted by, and thus be used as an observational constraint for various parameters such as initial mass, rotation, and overshoot scheme. We investigate stellar models with varying initial mass as they evolve past the main sequence, and we examine the red supergiant (RSG) properties in detail. For each mass, we vary the initial rotation up to $\sim$ 300 $km\:s^{-1}$, and test two different overshoot parameters. Overall, the acceptable initial mass range is 12 to 25 $M_\odot$, but for non-rotating models only, the range is decreased to 15 to 24 $M_\odot$. Also for rotating models, we find that $v/v_{\rm K} = 0.3$ is the upper limit for initial rotation, as more rapidly rotating models are unable to fit to Betelgeuse's surface abundances as an RSG. In addition, we report two possibilities for the current stage of evolution, core helium burning or core carbon burning and beyond. We find that certain 17 $M_\odot$ models could fit to both stages. Finally, we discuss the implications of our results in the context of merger scenarios which have been suggested as a mechanism to attain the observed surface velocity of Betelgeuse.
