Open AccessOn the oscillations and the stability of a uniformly rotating gaseous gravitating disc, including viscosity and heat exchange
Author(s) -
Antonov V. A.,
Kondratyev B. P.
Publication year - 1999
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.1365-8711.1999.02276.x
Subject(s) - physics , dissipative system , classical mechanics , mechanics , instability , viscosity , perturbation (astronomy) , gravitation , thermodynamics , quantum mechanics
This paper presents a critical revision of the problem of small oscillations and stability of a thin, homogeneous and uniformly rotating gas disc, with regard to self‐gravitation, viscosity and dissipative factors. We allow for the possibility of heat exchange between this disc and the non‐equilibrium thermodynamic surrounding medium. A combined method for the study of discs is applied, which takes into account both the elements of the perturbation method and those of the variational description. The general dispersion equations of this task are obtained, and a careful analysis of these equations is carried out. We establish that dissipative factors lead to two completely different modes of slow instabilities. The first mode is the ordinary secular instability, and the other mode is an amplification of gravitational sound oscillations under heat exchange with the external medium. The criteria for these modes of instability of the disc are found.