Accretion shock geometries in the magnetic variables.
Abstract
This paper reviews self-consistent shock models for the AM Herculis-type systems. Observational evidence supports a non-homogeneous accretion profile which may extend over a considerable fraction of the stellar surface. The author reviews both the fundamental assumptions underlying the canonical 1-D shock model and the extension of this model to inhomogeneous accretion shocks for both radial and linear structures. The author also examines the observational evidence for "tall" shocks and finds little evidence for relative shock heights in excess of h/R1 ≥ 0.1. For several systems upper limits to the shock height can be obtained from either X-ray or optical data. These lie in the region h/R1 ⪉ 0.01, and are in general agreement with the current physical picture for these systems. The quasi-periodic optical variations observed in several magnetic variables may eventually prove to be a major aid in further understanding their accretion shock geometries.
- Publication:
-
Polarized Radiation of Circumstellar Origin
- Pub Date:
- 1988
- Bibcode:
- 1988prco.book..237S
- Keywords:
-
- Accretion Disks;
- Cataclysmic Variables;
- Magnetic Stars;
- Polarized Radiation;
- Shock Waves;
- Stellar Systems;
- Canonical Forms;
- Circular Polarization;
- Stellar Interiors;
- Stellar Luminosity;
- Stellar Models;
- Visible Spectrum;
- Astrophysics;
- Cataclysmic Binaries: Magnetic Stars;
- Cataclysmic Binaries: Accretion;
- White Dwarfs: Accretion