THE GALAXY POPULATION IN THE CLUSTER CL-1409-295)(524 (3C)

We observed the cluster Cl 1409+524 (z=0.46) with an imaging Fabry-Per ot interferometer. A sequence of Fabry-Perot images (FWHM=1.0-1.3 nm) was used to search for red-shifted [O II]lambda372.7 nm- and [O III]la mbda500.7 nm line emission. We studied 144 galaxies up to a limiting c ontinuum R-band magnitude of 22.5 mag within 1 Mpc around the cluster center. Previously known emission-line galaxies in the cluster were co nfirmed and 17 new members with emission lines were found. Their star formation rate of 1-2 M.yr-1 is typical for normal spirals. We have im aged the cluster with broad band B, R and seven intermediate band filt ers (FWHM=10.0-20.0 nm) in order to derive low-resolution spectral ene rgy distributions of cluster galaxies. These were fitted by template s pectra to estimate Hubble class and redshifts. Based on this decomposi tion, we derived a percentage of emission-line galaxies of 40+/-11%.