Connecting galaxy structure and star formation: the role of environment
  in formation of S0 galaxies
  In this work, we investigate the reason behind the increased occurrence of S0
galaxies in high density environments. Our sample comprises of $\sim$ 2500
spiral and $\sim$ 2000 S0 galaxies spanning a wide range of environments.
Dividing the galaxies into categories of classical and pseudobulge hosting
spiral and S0 galaxies, we have studied their properties as a function of the
environment. We find that the fraction of pseudobulge hosting disc galaxies
decreases with increase in density. The classical bulge hosting spirals and S0
galaxies follow a similar trend in less dense environments but towards higher
densities, we observe an increase in the fraction of classical bulge host S0
galaxies at the expense of spirals. Comparing the structural and the star
formation properties of galaxies on the size-mass and $NUV-r$ colour-mass
planes respectively, we infer that classical bulge hosting spirals are likely
to get transformed into S0 morphology. We notice a trend of galaxy structure
with environment such that the fraction of classical bulge hosting spiral
galaxies is found to increase with environment density. We also find that among
classical bulge hosting spirals, the fraction of quenched galaxies increases in
denser environments. We surmise that the existence of more classical bulge
hosting spirals galaxies and more efficient quenching leads to the observed
increased occurrence of S0 galaxies in high density environments. The relation
between galaxy structure and environment also exists for the disc galaxies
irrespective of their visual morphology, which is driven mainly by halo mass.
