The nuclear X-ray source in M 81.
Abstract
X-ray observations of the M81 galaxy were taken by the high resolution imager and the monitor proportional counter aboard the Einstein observatory. The luminosity is about 1.7 X 10 to the 40th ergs/s. It is suggested that M81 probably has an active nucleus two orders of magnitude less luminous than any other well-established case. Any critical 'turn-on' luminosity is thus very low and approaches that of compact X-ray binary systems. The agreement of the alpha hydrogen/X-ray ratio of M81 suggests that the physics of the activity is not strongly different at these low luminosities from that in the normal range
- Publication:
-
The Astrophysical Journal
- Pub Date:
- June 1982
- DOI:
- 10.1086/183807
- Bibcode:
- 1982ApJ...257L..51E
- Keywords:
-
- Galactic Nuclei;
- Luminosity;
- Seyfert Galaxies;
- X Ray Sources;
- High Resolution;
- Point Sources;
- Proportional Counters;
- Astronomy