The excitation and physical nature of megamasers.
Abstract
The mechanisms for creating inversion in OH megamasers are analyzed. It is shown that far-IR radiation at 53 microns in a turbulent medium with a velocity of 0.7 km/s or greater and n = 1000/cu cm, under the condition T(rad) is greater than T(kin), is most likely to be the pumping mechanism of the radio lines of the ground state of the OH molecule. Emission in the radio lines of the ground rotational state J = 1/2 2Pi1/2 of CH molecules should be observable from some IRAS galaxies. The kinematics of clouds moving from or toward an active nucleus are discussed.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- May 1990
- Bibcode:
- 1990MNRAS.244...86B
- Keywords:
-
- Hydroxyl Emission;
- Interstellar Masers;
- Molecular Clouds;
- Spiral Galaxies;
- Water Masers;
- Far Infrared Radiation;
- Infrared Astronomy Satellite;
- Molecular Rotation;
- Radio Emission;
- Astrophysics