The Infrared and Optical Pulsations of G29-38
Abstract
High-speed infrared photometry at 1.25, 2.2, and 3.5 microns of the pulsating white dwarf G29 - 38 reveals the presence of unexpectedly large amplitude signals at 2.2 microns, with periods of 186, 243, and 268 s. Simultaneous optical coverage demonstrates the presence of signals of identical period and phase in blue light, which proves that they are ultimately seated in the white dwarf, not in the cool component known to be present in the system. But their anomalously high amplitude in the infrared suggests either a breakdown of stellar atmosphere theory or a process by which the pulsating white dwarf can very efficiently excite an oscillation in the cool component. A model is discussed in which a dusty ring reprocesses the incident radiation from the white dwarf, assumed to contain both east-west and north-south pulsations. The model has some heuristic value but requires a very special geometry to satisfy the observations.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- June 1991
- DOI:
- Bibcode:
- 1991ApJ...374..330P
- Keywords:
-
- Binary Stars;
- Infrared Photometry;
- Stellar Oscillations;
- White Dwarf Stars;
- Cool Stars;
- Light Curve;
- Power Spectra;
- Astrophysics;
- STARS: BINARIES;
- STARS: INDIVIDUAL ALPHANUMERIC: G29-38;
- STARS: PULSATION;
- STARS: WHITE DWARFS