Infrared Properties of OH Galaxies
Abstract
The far-infrared (FIR) characteristics of extragalactic OH megamasers and OH absorbers are compared and interpreted. Although both groups require edge-on molecular disk systems, the OH megamasers occur in galaxies with large FIR luminosities L_IR_ and OH absorption in galaxies with lower L_IR_. The OH luminosity of the observed megamasers varies with L^2^_IR_, which is in agreement with the predictions of a model for megamasers having IR-pumped molecular gas amplifying background radio continuum. The proposed pumping scheme relying on the FIR radiation field in the galaxy is generally confirmed. A prediction of the numbers of detectable OH megamasers based on the known properties of megamasers and of luminous FIR sources is in good agreement with the numbers of detected masers. It is more likely to detect a distant luminous maser than a nearby weak one; there is no large detectable population of weak OH megamasers.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- March 1989
- DOI:
- 10.1086/167237
- Bibcode:
- 1989ApJ...338..804B
- Keywords:
-
- Galaxies;
- Hydroxyl Emission;
- Infrared Astronomy;
- Interstellar Masers;
- Water Masers;
- Absorption Spectra;
- Emission Spectra;
- Interstellar Matter;
- Luminosity;
- Radiation Distribution;
- Astrophysics;
- GALAXIES: INTERSTELLAR MATTER;
- INFRARED: SOURCES;
- MASERS