Properties of quasi-periodic oscillations in accreting magnetic white dwarfs

Details Properties of quasi-periodic oscillations in accreting magnetic white dwarfs Properties of quasi-periodic oscillations in accreting magnetic white dwarfs

Sep 1992

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1992apj...397..232w&link_type=abstract

Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 397, no. 1, p. 232-241.

Other

26

Accretion Disks, Bremsstrahlung, Stellar Magnetic Fields, Stellar Oscillations, White Dwarf Stars, Cyclotron Radiation, Harmonics, Luminosity, Stellar Mass Accretion

Scientific paper

Previous studies of time-dependent accretion onto magnetic white dwarfs, in which the cooling was assumed to be due to bremsstrahlung emission, have shown that the accretion shock undergoes oscillations. However, when cyclotron cooling is also included, the oscillations are damped for sufficiently strong magnetic fields. Here we demonstrate that the oscillations can be sustained by accretion-fluctuation-induced excitations. The frequency of the QPOs are shown to increase quadratically with the magnetic field strength. We interpret the oscillations as a two-phase process in which bremsstrahlung cooling dominates in one half-cycle and cyclotron cooling in the other. Such a process may have very different consequences compared to a single-phase process where the functional form of the cooling is essentially the same throughout the cycle. If in the two-phase process damping occurs mainly in the cyclotron cooling half-cycle, there will be a universal effective damping factor which tends to suppress all oscillation modes indiscriminately. The oscillations of the accretion shock also could be a limit cycle process in which the system vacillates between two branches.

Affiliated with

Also associated with

No associations

Rating

Properties of quasi-periodic oscillations in accreting magnetic white dwarfs does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Properties of quasi-periodic oscillations in accreting magnetic white dwarfs, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Properties of quasi-periodic oscillations in accreting magnetic white dwarfs will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1766222