What is the optimum stellar rotation rate for a collapsar?
نویسندگان
چکیده
— 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 ≃ 2rgc.
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