The Effect of Progressive Sound Waves on the Profiles of Stellar Spectral Lines
Abstract
Progressive sound waves propagating through a region of spectral4ine formation in a stellar atmosphere are considered The sound wave sets the atoms in oscillatory motion While thus performing an ordered motion, the atoms will emit or absorb radiation if properly excited. The radiation will be absorbed (emitted) at a Doppler-shifted wavelength, the Doppler shift being determined by the velocity given to the radiating atoms by the wave The sound wave will also alter the density of atoms capable of absorbing or emitting the line in question. The effect (integrated over one period) of progressive sound waves on the shape of spectral lines is calculated in a few simple cases where the line depth is assumed proportional to the line-absorption coefficient The line profiles are found to be highly asymmetrical when the pressure amplitudes of the wave are relatively large. The degree of asymmetry of the line is found to increase with atomic weight of the atoms producing the line.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- June 1967
- DOI:
- 10.1086/149207
- Bibcode:
- 1967ApJ...148..833E