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We discuss the observational evidences of the morphological transformation of Spirals into S0 galaxies in the cluster environment exploiting two big databases of galaxy clusters: WINGS (0.04 < z < 0.07) and EDisCS (0.4 < z < 0.8). The most important results are: 1) the average number of S0 galaxies in clusters is almost a factor of $sim 3 - 4$ larger today than at redshift $z sim 1$; 2) the fraction of S0s to Spirals increases on average by a factor $sim$ 2 every Gyr; 3) the average rate of transformation for Spirals (not considering the infall of new galaxies from the cosmic web) is: $sim$ 5 Sp into S0s per Gyr and $sim$ 2 Sp into Es per Gyr; 4) there are evidences that the interstellar gas of Spirals is stripped by an hot intergalactic medium; 5) there are also indirect hints that major/minor merging events have played a role in the transformation of Spiral galaxies. In particular, we show that: 1) the ratio between the number of S0s and Spirals (NS0/NSp) in the WINGS clusters is correlated with their X-ray luminosity $L_X$ ; 2) that the brightest and massive S0s are always close to the cluster center; 3) that the mean Sersic index of S0s is always larger than that of Spirals (and lower than Es) for galaxy stellar masses above $10^9.5$ Msun; 4) that the number of Es in clusters cannot be constant; 5) that the largest difference between the mean mass of S0s and Es with respect to Spirals is observed in clusters with low velocity dispersion. Finally, by comparing the properties of the various morphological types for galaxies in clusters and in the field, we find that the most significant effect of the environment is the stripping of the outer galaxy regions, resulting in a systematic difference in effective radius and Sersic index.
By studying the individual star-formation histories of the bulges and discs of lenticular (S0) galaxies, it is possible to build up a sequence of events that leads to the cessation of star formation and the consequent transformation from the progenit
We present deep GMOS long-slit spectroscopy of 15 Coma cluster S0 galaxies, and extract kinematic properties along the major axis to several times the disc scale-length. Supplementing our dataset with previously published data, we create a combined s
We present an analysis of V-band radial surface brightness {mu}(r) profiles for S0s in different environments using HST/ACS imaging and data from the Space Telescope A901/2 Galaxy Evolution Survey (STAGES). Using a sample of ~280 field and cluster S0
The influence of the environment on the polarized and total power radio continuum emission of cluster spiral galaxies is investigated. We present deep scaled array VLA 20 and 6 cm observations including polarization of 8 Virgo spiral galaxies. These
We use integral field spectroscopy of 13 disk galaxies in the cluster AC114 at z ~ 0.31 in an attempt to disentangle the physical processes responsible for the transformation of spiral galaxies in clusters. Our sample is selected to display a dominan