Open AccessThe radial–azimuthal instability of a hot two‐temperature accretion disc with advection
Author(s) -
ShiXue Ding,
LanTian Yang,
XueBing Wu,
Ye Lu
Publication year - 2000
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.2000.03392.x
Subject(s) - physics , advection , instability , wavenumber , azimuth , perturbation (astronomy) , mechanics , wavelength , temperature gradient , thermal , classical mechanics , astrophysics , optics , thermodynamics , meteorology , quantum mechanics
The radial–azimuthal instability of a hot two‐temperature accretion disc with advection is examined in this paper. We find that the inclusion of very little advection has significant effects on two acoustic modes for a geometrically thin, cooling‐dominated two‐temperature disc, but has no effect on acoustic modes for a geometrically slim, cooling‐dominated two‐temperature disc. We also find that, when azimuthal perturbations are considered, the stability properties of the disc are different from those in the pure radial perturbation case. An increase of the azimuthal wavenumber will stabilize the acoustic modes but make the viscous and thermal modes more unstable for a geometrically thin, cooling‐dominated two‐temperature disc. It makes the thermal mode more unstable and the acoustic mode more stable, but only affects the instability of the viscous mode for short‐wavelength perturbations for a geometrically slim, cooling‐dominated two‐temperature disc. For a geometrically slim, advection‐dominated two‐temperature disc, the increase of the azimuthal perturbation makes the I‐ and O‐modes more stable and the thermal mode more unstable, but has no effect on the viscous mode.