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The collapse of gas discs in non-axisymmetric galaxy cores

R. H. Sanders
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Abstract

Below a threshold energy, gas in the constant density core of a triaxial galaxy can find no simple non-intersecting periodic orbit to act as an attractor for its trajectory (El-Zant et al. 2003). If a disc of gas arriving from further out in the galaxy dissipates sufficient energy to fall below this threshold, it will thereafter collapse into the very centre. Such a mechanism may be relevant to the early growth of super-massive black holes at the Eddington limit and the appearance of the quasar phenomenon at high redshift. This process is self-limiting in the sense that, when the black hole mass has grown to a significant fraction of the core mass, simple angular momentum conserving orbits are restored and accretion reverts to the slow viscous mode. The mechanism depends upon the pre-existence of constant density cores in triaxial spheroidal galaxies.

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R. H. Sanders. 2006-12-18. The collapse of gas discs in non-axisymmetric galaxy cores. https://arxiv.org/abs/astro-ph/0612095

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