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Maximum Accretion Efficiency in General Theory of Relativity

Abhas Mitra
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Abstract

We derive here the expression for the accretion luminosity, $L(\infty)$, as seen by a distant inertial observer $S_\infty$, for the case of spherical accretion onto a static compact object having a surface gravitational red-shift $z_x$. It is found that the ``efficiency'' for conversion of mass energy into accretion energy is given by $ε= z_x/(1+z_x)$. And since the maximum value of $z_x$ permitted by General Theory of Relativity (GTR) is 2, the maximum theoretical value of the accretion efficiency is 66.66%.

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Abhas Mitra. 1998-11-25. Maximum Accretion Efficiency in General Theory of Relativity. https://arxiv.org/abs/astro-ph/9811402

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