Frequency Stability of the Cooler Pulsating White Dwarfs

Gravitational Radiation from Pulsating White Dwarfs

Rotating white dwarfs undergoing quasi-radial oscillations can emit gravitational radiation in a frequency range from 0.1 − 0.3 Hz. Assuming that the energy source for the gravitational radiation comes from the oblateness of the white dwarf induced by the rotation, the strain amplitude is found to be ∼ 10 for a white dwarf at ∼ 50 pc. The galactic population of these sources is estimated to be ...

Mode identification of Pulsating White Dwarfs using the HST 1

Seismology of pre-white dwarfs: Models for pulsating sdB stars

Two kinds of pre-white dwarf stars can be probed through asteroseismology: planetary nebula nuclei (PNNs) and sdB (EHB) stars. To exploit the observed pulsations requires models that incorporate state-ofthe-art input physics and realistic evolutionary histories. Pulsation analysis of extensive grids of such models provide self-consistent theoretical pulsation periods for comparison with observe...

Pulsating young brown dwarfs

We present the results of a nonadiabatic, linear stability analysis of models of very low-mass stars (VLMSs) and brown dwarfs (BDs) during the deuterium burning phase in the center. We find unstable fundamental modes with periods varying between ∼5 hr for a 0.1 M⊙ star and ∼1 hr for a 0.02 M⊙ BD. The growth time of the instability decreases with decreasing mass and remains well below the deuter...

Pulsating White Dwarfs in Cataclysmic Variables: The Marriage of ZZ Cet and Dwarf Nova

There are now four dwarf novae known with white dwarf primaries that show large amplitude non-radial oscillations of the kind seen in ZZ Cet stars. We compare the properties of these stars and point out that by the end of the Sloan Digital Sky Survey more than 30 should be known.