A formaldehyde maser in NGC 7538.
Abstract
The formaldehyde emission at 4.8 GHz in NGC 7358 is located at the position of the compact radio and infrared source IRS1. The angular size of the H2CO source is less than 4 arcsec, which indicates a minimum line brightness temperature of 800 K. This limit, and the non-detection of the H2CO line at 14.5 GHz, rules out a thermal explanation, and the H2CO emission source must be a maser. Because of the agreement in radial velocities, the H2CO maser features may be emitted in the same region as the 1720 MHz OH maser lines.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- April 1980
- Bibcode:
- 1980A&A....84L...1F
- Keywords:
-
- Formaldehyde;
- Hydrogen Clouds;
- Interstellar Masers;
- Absorption Spectra;
- Astronomical Maps;
- Brightness Temperature;
- Data Reduction;
- Emission Spectra;
- Microwave Spectra;
- Radial Velocity;
- Astrophysics