Upper and lower bounds of periods in variable white dwarfs. (original) (raw)

NASA/ADS

;

• Winget, D. E. ;
• Kawaler, S. D.

Abstract

Upper and lower critical frequencies for adiabatic radial and nonradial oscillations of white dwarfs are established. The ranges of pulsation frequency where wave leakage may occur are estimated, and the importance of that leakage for damping pulsation is considered. It is found that acoustic modes are strongly damped by outwardly propagating running waves in the atmosphere when periods are less than 0.1-1 sec. For gravity modes, a similar result holds when periods exceed a certain approximate value. Applications to observed white dwarf variable periods are discussed.

Publication:

The Astrophysical Journal

Pub Date:

October 1985

DOI:

10.1086/163549

Bibcode:

1985ApJ...297..544H

Keywords:

• Boundary Value Problems;
• Critical Frequencies;
• Stellar Oscillations;
• Variable Stars;
• White Dwarf Stars;
• Adiabatic Conditions;
• Gravity Waves;
• Sound Waves;
• Stellar Atmospheres;
• Wave Attenuation;
• Astrophysics