We have carried out an investigation of the properties of low redshift EIS clusters using both spectroscopy and imaging data .
We present new redshifts for 738 galaxies in 21 ESO Imaging Survey ( EIS ) Cluster fields .
We use the “ gap ” -technique to search for significant overdensities in redshift space and to identify groups/clusters of galaxies corresponding to the original EIS matched filter cluster candidates .
In this way we spectroscopically confirm 20 of the 21 cluster candidates with a matched-filter estimated redshift z _ { MF } = 0.2 .
We have now obtained spectroscopic redshifts for 34 EIS cluster candidates with z _ { MF } = 0.2 ( see also ) .
Of those we spectroscopically confirm 32 with redshifts ranging from z = 0.064 to 0.283 .
We find that : 1 ) the velocity dispersions of the systems range from \sigma _ { v } \leq 130 \mathrm { km / s } to \sigma _ { v } = 1200 \mathrm { km / s } , typical of galaxy groups to rich clusters ; 2 ) richnesses corresponding to Abell classes R \leq 1 ; and 3 ) concentration indices ranging from C = 0.2 to C = 1.2 .
From the analysis of the colours of the galaxy populations we find that 53 % of the spectroscopically confirmed systems have a “ significant ” red sequence .
These systems are on average richer and have higher velocity dispersions .
We find that the colour of the red sequence galaxies matches passive stellar evolution predictions .