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What is the optimum stellar rotation rate for a collapsar?

William H. Lee
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Abstract

We consider low angular momentum, neutrino cooled accretion flows onto newborn black holes in the context of the collapsar model for long Gamma Ray Bursts, and find a considerable energy release for rotation rates lower than those usually considered. The efficiency for the transformation of gravitational binding energy into radiation is maximized when the equatorial angular momentum l0 ~ 2 Rg c, where Rg is the Schwarzschild radius.

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William H. Lee. 2007-03-01. What is the optimum stellar rotation rate for a collapsar?. https://doi.org/10.1393/ncb%2Fi2007-10076-5

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