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arXiv 1804.07486astro-ph.HEastro-ph.SR
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恒星风对Cosmic Ray产生的贡献

The Contribution of Stellar Winds to Cosmic Ray Production

Jeongbhin Seo, Hyesung Kang, Dongsu Ryu

摘要:

大质量恒星在从主序星到沃尔夫-拉叶星的整个演化阶段都吹着强大的恒星风。大质量恒星的恒星风在星际介质中沉积的机械能相当于一颗在其生命结束时爆炸的核心坍缩超新星的爆炸能量。在这项研究中,我们估计的动能沉积的大质量恒星在我们的银河系考虑的综合初始质量函数和模拟的恒星风光度。采用理论计算和已有的观测资料,估算了主序星、红超巨星和Wolf-Rayet阶段星风的质量损失率和终极速度。我们发现银河系中所有大质量恒星产生的总恒星风光度约为$L_w\approx 1.1\times 10^{41}$ erg/s,约为超新星爆发功率$L_{SN} \approx 4.8\times 10^{41}$ erg/s的1/4。如果我们假设风光度的$\sim 1-10$ %可以通过无碰撞的激波(如恒星泡和超级泡中的终止激波、双星中的碰撞风激波和大质量逃逸恒星的弓形激波)转化为银河系宇宙射线(GCR),那么恒星风可能会对GCR的产生做出重大贡献,尽管低于超新星遗迹的贡献。

英文摘要:

Massive stars blow powerful stellar winds throughout their evolutionary stages from the main sequence to Wolf-Rayet phases. The amount of mechanical energy deposited in the interstellar medium by the wind from a massive star can be comparable to the explosion energy of a core-collapse supernova that detonates at the end of its life. In this study, we estimate the kinetic energy deposition by massive stars in our Galaxy by considering the integrated Galactic initial mass function and modeling the stellar wind luminosity. The mass loss rate and terminal velocity of stellar winds during the main sequence, red supergiant, and Wolf-Rayet stages are estimated by adopting theoretical calculations and observational data published in the literature. We find that the total stellar wind luminosity due to all massive stars in the Galaxy is about $L_w\approx 1.1\times 10^{41}$ erg/s, which is about 1/4 of the power of supernova explosions, $L_{SN} \approx 4.8\times 10^{41}$ erg/s. If we assume that $\sim 1-10$ % of the wind luminosity could be converted to Galactic cosmic rays (GCRs) through collisonless shocks such as termination shocks in stellar bubbles and superbubbles, colliding-wind shocks in binaries, and bow-shocks of massive runaway stars, stellar winds might be expected to make a significant contribution to GCR production, though lower than that of supernova remnants.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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