H-alpha luminosity and star formation of galaxies in Hickson Compact Groups

We have obtained H alpha fluxes and luminosities for a sample of 95 galaxie s from observations of 31 Hickson Compact Groups (HCGs) in the northern hem isphere. This sample is the largest H alpha selected catalogue of galaxies having H alpha calibrated fluxes so far. The results obtained from a prelim inary analysis of a subsample of 66 galaxies show that the H alpha luminosi ty of the galaxies is correlated with velocity dispersion and compactness o f groups. These correlations would point towards a scenario in which the br ightest H alpha galaxies reside in compact groups having higher probability of galaxy interaction, i.e. lower values of velocity dispersion. Moreover, such relations seem to depend on the environment in which HCGs themselves are embedded.