Masers.
Abstract
Observations and theories that describe the characteristics of interstellar masers are described, with particular attention given to what has been and can be learned about star formation through the study of masers. Then, observations and theories pertaining to stellar masers are examined, with emphasis on the information maser emission can provide about these evolved stars and their mass loss. Attention is then given to radiative transfer theory as developed for astronomical masers; saturation, the apparent brightness distribution of the emission, the source of the input radiation that is amplified, and pump mechanisms are considered. The use of masers as probes of the electron distribution in the interstellar medium by means of scattering is reviewed. Finally, consideration is given to the recent measurements of proper motions of H2O masers and to the use of masers as direct indicators of galactic and extragalactic distances through trigonometric and statistical parallax measurements.
- Publication:
-
Annual Review of Astronomy and Astrophysics
- Pub Date:
- 1981
- DOI:
- Bibcode:
- 1981ARA&A..19..231R
- Keywords:
-
- Interstellar Masers;
- Interstellar Radiation;
- Radiative Transfer;
- Stellar Evolution;
- Water Masers;
- Electron Distribution;
- Microwave Probes;
- Microwave Scattering;
- Radiation Distribution;
- Saturation;
- Stellar Models;
- Astrophysics