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arXiv · 1209.1104

Accumulated Tidal Heating of Stars Over Multiple Pericenter Passages Near SgrA*

Gongjie Li·Abraham Loeb
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Abstract

We consider the long-term tidal heating of a star by the supermassive black hole at the Galactic center, SgrA*. We show that gravitational interaction with background stars leads to a linear growth of the tidal excitation energy with the number of pericenter passages near SgrA*. The accumulated heat deposited by excitation of modes within the star over many pericenter passages can lead to a runaway disruption of the star at a pericenter distance that is 4-5 times farther than the standard tidal disruption radius. The accumulated heating may explain the lack of massive ($\gtrsim 10M_{\odot}$) S-stars closer than several tens of AU from SgrA*.

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Gongjie Li, Abraham Loeb. 2012-09-05. Accumulated Tidal Heating of Stars Over Multiple Pericenter Passages Near SgrA*. https://doi.org/10.1093/mnras/sts567

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