Core-Collapse Very Massive Stars: Evolution, Explosion, and Nucleosynthesis of Population III 500-1000 M☉ Stars
Core-Collapse Very Massive Stars: Evolution, Explosion, and Nucleosynthesis of Population III 500-1000 M☉ Stars
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核心塌陷超大质量恒星：星族 III 500-1000 M☉ 恒星的演化、爆炸和核合成
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发表时间：
2005
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通讯作者：
M. Rees
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作者：
T. Ohkubo;H. Umeda;K. Maeda;K. Nomoto;Tomoharu Suzuki;S. Tsuruta;M. Rees
我们计算了星族III中500和1000 M的超大质量恒星的演化、坍缩、爆炸和核合成。超新星前的演化是在球对称中计算的。在双极射流模型的基础上，用二维程序计算了坍塌和爆炸。我们比较了核合成的结果与星系团内物质、M82中的热气体和银河系晕中极贫金属恒星的丰度模式。结果发现，500和1000 M的两个模型进入对不稳定的区域，但继续进行核心崩溃。在前超新星阶段，硅燃烧区占据了很大一部分，超过总质量的20%。对于中度非球面爆炸，核合成的模式与星团内介质和M82的观测数据相匹配。我们的研究结果表明，第三族核心坍缩的大质量恒星的爆炸对星系团中气体的化学演化有显着的贡献。对于银河系晕星，我们的[O/Fe]比小于观测丰度。然而，我们提出的设想自然与这一结果相一致。对于500和1000 M的黑洞模型，最终的黑洞质量分别为~230和~500 M。这一结果可能支持这样的观点，即第三星族的超大质量恒星是最近发现的中等质量黑洞的起源。
We calculate evolution, collapse, explosion, and nucleosynthesis of Population III very massive stars with 500 and 1000 M☉. Presupernova evolution is calculated in spherical symmetry. Collapse and explosion are calculated by a two-dimensional code, based on the bipolar jet models. We compare the results of nucleosynthesis with the abundance patterns of intracluster matter, hot gases in M82, and extremely metal-poor stars in the Galactic halo. It was found that both 500 and 1000 M☉ models enter the region of pair instability but continue to undergo core collapse. In the presupernova stage, silicon-burning regions occupy a large fraction, more than 20% of the total mass. For moderately aspherical explosions, the patterns of nucleosynthesis match the observational data of both the intracluster medium and M82. Our results suggest that explosions of Population III core-collapse very massive stars contribute significantly to the chemical evolution of gases in clusters of galaxies. For Galactic halo stars our [O/Fe] ratios are smaller than the observational abundances. However, our proposed scenario is naturally consistent with this outcome. The final black hole masses are ~230 and ~500 M☉ for the 500 and 1000 M☉ models, respectively. This result may support the view that Population III very massive stars are responsible for the origin of intermediate-mass black holes, which were recently reported to be discovered.