Pseudo-Newtonian and general relativistic barotropic tori in Schwarzschild-de Sitter spacetimes
Autor/ři
Z. Stuchlík, P. Slaný, J. Kovář
Publikováno
Classical and Quantum Gravity, (2009), vol. 26, 21, p. 215013--215047
Rok
2009
Abstrakt
Pseudo-Newtonian gravitational potential introduced in spherically
symmetric black-hole spacetimes with a repulsive cosmological constant is tested
for equilibrium toroidal configurations of barotropic perfect fluid orbiting the black
holes. Shapes and potential depths are determined for the marginally stable
barotropic tori with uniform distribution of specific angular momentum, using
both the pseudo-Newtonian and fully relativistic approach. For the adiabatic
(isoentropic) perfect fluid, temperature profiles, mass-density and pressure profiles
and total masses of pseudo-Newtonian and relativistic tori are compared providing
important information on the relevance of the test-disc approximation in both
the approaches. It is shown that the pseudo-Newtonian approach can be precise
enough and useful for the modelling of accretion discs in the Schwarzschild-de
Sitter spacetimes with the cosmological parameter y = ΛM 2 /3 10−6 . For
astrophysically relevant black holes with y < 10−25 , this statement is tested and
shown to be precise in few percent for both accretion and excretion tori and for
the marginally bound, i.e., maximally extended tori allowing simultaneous inflow
to the black hole and outflow to the outer space.
Soubor(y)



