Low mass portion of the galaxy clustering spectrum

Abstract

To understand the physical processes which controlled the formation of individual galaxies and clusters of galaxies, it is very important to determine the relative numbers of clusters over a wide range of masses. Although this present day clustering spectrum may not perfectly match the primordial spectrum, one hopes that the major features of the latter might be deduced from the observations. For the massive end of the clustering spectrum, the catalogue of Abell¹ can be analysed to provide the necessary data². For the faint end there are many problems, both observational and theoretical. The observational problems arise if attempts are made to specify group or cluster membership when insufficient data are available. These problems can be avoided by using a complete redshift survey. We have previously presented a large redshift survey of galaxies in a 260 deg² region of the sky in the direction of the rich clusters Coma and A1367. We found eight groups and clouds which lie in the 4.2 × 10⁴ Mpc³ (assuming H₀ = 50 km s⁻¹ Mpc⁻¹) between the local supercluster and the Coma/A1367 supercluster. We use this new survey data here to determine the low mass portion of the clustering spectrum.