of their progenitor protogalaxies is the principal parameter governing their evolution. Massive systems having high initial efficiency of collapse, or a short collapse time-scale, have retained little gas to feed the present epoch of star formation. These findings support the conclusions of Gavazzi & Scodeggio (1996) who studyed the color-mass relation of a local galaxy sample and agree with the analysis by Cowie et al. (1996) who traced the star formation history of galaxies up to z$>$1.
author:
- Giuseppe Gavazzi and Barbara Catinella
- Luis Carrasco
- Alessandro Boselli
- Alessandra Contursi
title: 'The star formation properties of disk galaxies: $\rm H\alpha$ imaging of galaxies in the Coma supercluster[^1]'
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Introduction
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Two major aspects of the phenomenology of disk galaxies, with relevant implications on the theory of galaxy formation and evolution, are still hotly debated among the scientific community: (i) whether the color-luminosity relation, well established among late-type galaxies, follows from a population sequence, as proposed by Gavazzi, Pierini & Boselli (1996) (hereafter GPB96) and by Gavazzi & Scodeggio (1996) (hereafter GS96), as opposite to a metallicity sequence (see Visvanathan 1991; Bothun et al. 1984), which appears to be the case in elliptical galaxies (see Arimoto & Kodama, 