ENVIRONMENTAL-EFFECTS ON THE COMA CLUSTER LUMINOSITY FUNCTION

Using our catalogue of V-26.5 isophotal magnitudes for 6756 galaxies i n a region covering 60 x 25 arcmin(2) in the center of the Coma cluste r, plus 267 galaxies in a region of 9.7 x 9.4 arcmin(2) around NGC 483 9, we derive the luminosity function in the magnitude range 13.5< V-26 .5 less than or equal to 21.0 (Corresponding to the absolute magnitude range -22.24 < M(V26.5) less than or equal to -14.74). The luminosity function for this region is well fitted by the combination of a gauss ian in its bright part and of a steep Schechter function (of index alp ha = -1.8) in its faint part. Luminosity functions derived for individ ual regions surrounding the brightest galaxies show less steep slopes, strongly suggesting the existence of environmental effects. The impli cations of such effects on galaxy formation scenarios are discussed.