Open AccessHydrodynamic simulations of cataclysmic variable accretion discs in outburst
Author(s) -
Stehle R.
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.1365-8711.1999.02391.x
Subject(s) - physics , astrophysics , accretion (finance) , cataclysmic variable star , radius , magnetorotational instability , accretion disc , intermediate polar , dwarf nova , orbital plane , astronomy , stars , white dwarf , magnetohydrodynamics , magnetic field , computer security , quantum mechanics , computer science
We study the outburst phase of cataclysmic variable (CV) accretion discs in the ( r , π) plane with full hydrodynamics. Vertically the disc is treated using the one‐zone model of Stehle & Spruit, which allows us to follow the fundamental mode of vertical disc oscillations correctly. α‐type shear viscosity (Shakura & Sunyaev) and energy loss at the surface of the accretion disc by radiation are included. We run accretion disc models with different masses M 1 and M 2 for the primary and the secondary stars and different values of α. In all calculations we observe strong spiral shock arms, which dominate the disc evolution on a hydrodynamical time‐scale. In cases where the surface mass density Σ (r) decreases with radius r the disc pattern is stable. In cases where Σ (r) increases with r we observe a quasi‐periodic cycle of disc size. During the phase where the disc is large, the spiral arm close to the L 1 point connects to the secondary, and about 1 per cent of the total disc mass is lost to the secondary per cycle. However, in none of our calculations are we able to find an eccentric and precessing accretion disc, even though the disc edge is outside the 3:1 tidal resonance radius R 31 . Our calculations therefore cannot confirm the tidal instability model, presently the only model for superhumps in SU UMa CVs during superoutbursts.