Detection of NH3 Molecules in the Interstellar Medium by Their Microwave Emission
Abstract
Ammonia has been found in the direction of the galactic center by detection of its J=1, K=1 inversion transition. The region of emission closely corresponds to the position, velocity, and size of strong OH absorption. Collisional and radiative excitation mechanisms are discussed. The column density of NH3 and the kinetic temperature of the interstellar gas cloud are estimated to be 2×1016/cm2 and 23°K, respectively.
- Publication:
-
Physical Review Letters
- Pub Date:
- December 1968
- DOI:
- 10.1103/PhysRevLett.21.1701
- Bibcode:
- 1968PhRvL..21.1701C