Effects of lower boundary conditions on the stability of radiative shocks
arXiv:astro-ph/0203412 · doi:10.1071/AS02004
Abstract
Thermal instabilities can cause a radiative shock to oscillate, thereby modulating the emission from the post-shock region. The mode frequencies are approximately quantised in analogy to those of a vibrating pipe. The stability properties depend on the cooling processes, the electron-ion energy exchange and the boundary conditions. This paper considers the effects of the lower boundary condition on the post-shock flow, both ideally and for some specific physical models. Specific cases include constant perturbed velocity, pressure, density, flow rate, or temperature at the lower boundary, and the situation with nonzero stationary flow velocity at the lower boundary. It is found that for cases with zero terminal stationary velocity, the stability properties are insensitive to the perturbed hydrodynamic variables at the lower boundary. The luminosity responses are generally dependent on the lower boundary condition.
17 pages, 2 figures, 3 tables; PASA in press
References in corpus (2)
Cited by in corpus (8)
- Instability of a stalled accretion shock: evidence for the advective-acoustic cycle
- Oscillations of MHD shock waves on the surfaces of T Tauri stars
- The Dynamics of Radiative Shock Waves: Linear and Nonlinear Evolution
- The Shocking Properties of Supersonic Flows: Dependence of the Thermal Overstability on M, alpha, and T_c/T_0
- Quasi-periodic oscillations in accreting magnetic white dwarfs I. Observational constraints in X-ray and optical
- Spherical accretion: the influence of inner boundary and quasi-periodic oscillations
- Estimation of Plasma Parameters in an Accretion Column near the Surface of Accreting White Dwarfs from Their Flux Variability
- Magnetized SASI: its mechanism and possible connection to some QPOs in XRBs