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arXiv · 1704.00433

Gravitational Collapse of Rotating Supermassive Stars including Nuclear Burning Effects

Haruki Uchida·Masaru Shibata·Takashi Yoshida·Yuichiro Sekiguchi·Hideyuki Umeda
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Abstract

Supermassive stars (SMSs) of mass $\gtrsim 10^5 M_\odot$ are candidates for seeds of supermassive black holes found in the center of many massive galaxies. We simulate the gravitational collapse of a rigidly rotating SMS core including nuclear burning effects in axisymmetric numerical-relativity simulation. We find that for realistic initial conditions, the nuclear burning does not play an important role. After the collapse, a torus surrounding a rotating black hole is formed and a fraction of the torus material is ejected. We quantitatively study the relation between the properties of these objects and rotation. We find that if a SMS core is sufficiently rapidly rotating, the torus and outflow mass have approximately $6\%$ and $1\%$ of the initial mass, respectively. The typical average velocity and the total kinetic energy of the outflow are $0.2~c$ and $10^{54-56}$ erg where $c$ is the speed of light. Finally, we briefly discuss the possibility for observing the torus and outflow.

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Haruki Uchida, Masaru Shibata, Takashi Yoshida, Yuichiro Sekiguchi, Hideyuki Umeda. 2017-04-03. Gravitational Collapse of Rotating Supermassive Stars including Nuclear Burning Effects. https://doi.org/10.1103/physrevd.96.083016

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