Distribution with Hα FWHM velocity, separated by ionization source and galaxy cluster dynamical state. Samples are matched in Hα luminosity and cluster-centric distance. The velocity width distribution of star formers is statistically distinct from that of AGNs. The bulk of star-forming galaxies, in both mergers and relaxed clusters, have narrow lines. On average, AGNs have broader velocity widths, extending above 400 km s⁻¹.