The enormous mass of the elliptical galaxy M87: a model for the extended X-ray source.
Abstract
It is suggested that the gas in M87 must be nearly in hydrostatic equilibrium and that the mass necessary to confine the hot gas to a scale height similar to that in X-ray observations is of the order of 100 trillion solar masses. Isothermal hydrostatic models for the gas are computed in which most of the mass in M87 is assumed to be situated in the outer regions of the galaxy. Attention is given to the parameters of the stellar component of the galaxy, matching of observed X-ray scans, the distribution of the dark matter in M87, absorption, and Faraday rotation. The thermal evolution of the hot gas is discussed, and it is concluded that the low-luminosity halo of M87 could account for most or all of the 'missing mass' of the Virgo cluster. The nature of the low-luminosity matter in M87 and the origin and fate of the hot gas are considered together with the nature of the gas in and near the galactic nucleus.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- January 1978
- DOI:
- 10.1086/155794
- Bibcode:
- 1978ApJ...219..413M
- Keywords:
-
- Astronomical Models;
- Elliptical Galaxies;
- Mass;
- X Ray Sources;
- Abundance;
- Faraday Effect;
- High Temperature Gases;
- Hydrostatics;
- Interstellar Gas;
- Isothermal Processes;
- Mass Distribution;
- Missing Mass (Astrophysics);
- Polarized Electromagnetic Radiation;
- Virgo Galactic Cluster;
- X Ray Astronomy;
- Astrophysics;
- Clusters of Galaxies:X-Ray Sources;
- Galaxies:Masses;
- M 87;
- Radio Galaxies:X-Ray Sources