Galaxy number counts and cosmology
Abstract
Using Cosmos machine measurements of UK Schmidt and Anglo-Australian telescope photographs in a blue and a red passband, galaxy number counts and color distribution to faint (B of about 23 mag) limits were obtained. The counts are compared with those of other authors and good agreement with the counts of Kron, Koo and Couch and Newell is found. Strong evidence is found for galaxy luminosity evolution in the blue counts and in the faint galaxy color distribution. The red counts show evidence for slower rates of galaxy luminosity evolution and, here, the effects of evolution and q(0) are comparable. The red count models are well enough determined to reject world models with q(0) not less than about 0.5, if galaxies were known to have undergone little luminosity evolution over a look-back time corresponding to a redshift of 0.5.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- February 1984
- DOI:
- 10.1093/mnras/206.4.767
- Bibcode:
- 1984MNRAS.206..767S
- Keywords:
-
- Color;
- Cosmology;
- Galactic Evolution;
- Galaxies;
- Luminosity;
- Astronomical Models;
- Astronomical Photography;
- Magnitude;
- Radial Velocity;
- Red Shift;
- Space Density;
- Astrophysics