Publication date: Apr 2019
Abstract:
We provide constraints on possible configurations and interactions of
two coplanar tori orbiting a central Kerr black hole (BH), in dependence
on its dimensionless spin. The two-tori configurations can be directly
linked to the current models featuring the obscuration of galactic BH
X-ray emission. The emergence of each torus instability phases is
discussed and tori collision has been also investigated. The first
simple evaluation of the center-of-mass energy proves that collision-
energy-efficiency increases with the dimensionless BH spin. We explore
the phenomenological aspects of the corotating and counterrotating tori
by analyzing properties of the orbiting toroidal configurations related
to the fluid enthalpy flux, the mass-flux, the mass-accretion-rates, and
the cusp luminosity in the two cases of corotating and counterrotating
fluids in dependence on the SMBH spin. The analysis resulted ultimately
in a comparative investigation of the properties of corotating versus
counterrotating tori, demonstrating that two accretion tori can orbit
around the central Kerr attractor only under very specific conditions.
Our results also demonstrate that the dynamics of the unstable phases of
these double tori systems is significant for the high energy phenomena
which could be observable in the X-ray emission and extremely energetic
phenomena in active galactic nuclei and quasar.
Authors:
Pugliese, D.; Stuchlík, Z.;