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Luminosity, selfgravitation and nonuniqueness of stationary accretion

Janusz Karkowski·Edward Malec·Krzysztof Roszkowski
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Abstract

We investigate newtonian description of accreting compact bodies with hard surfaces, including luminosity and selfgravitation of polytropic perfect fluids. This nonlinear integro-differential problem reduces, under appropriate boundary conditions, to an algebraic relation between luminosity and the gas abundance in stationary spherically symmetric flows. There exist, for a given luminosity, asymptotic mass and the asymptotic temperature, two sub-critical solutions that bifurcate from a critical point. They differ by the fluid content and the mass of the compact centre.

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Janusz Karkowski, Edward Malec, Krzysztof Roszkowski. 2006-11-13. Luminosity, selfgravitation and nonuniqueness of stationary accretion. https://arxiv.org/abs/astro-ph/0611393

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