PHOTOMETRY OF BRIGHTEST GALAXIES IN 20 ABELL CLUSTERS

CCD imaging and extractions from the Digitized Sky Survey were used to obtain photometry of the first- and second-ranked galaxies in twenty Abell galaxy clusters selected only on redshift (z<0.25) and richness (R>0). For each object, apparent magnitudes were calculated in circula r apertures with radii of 5h(-1) and 10h(-1) kpc and a total magnitude estimated using an elliptical isophote fitting routine. The distribut ion of absolute magnitudes in the 10h(-1) kpc radius aperture is consi stent with that found in previous work and can br described by a gauss ian with mean [M-1] = - 21.5 +/- 0.10 and dispersion sigma(M1) = 0.37 +/- 0.06. There is no evidence for significant luminosity evolution or dependence on cluster properties, although the small size of the samp le precludes definitive limits. (C) 1997 American Astronomical Society .