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[Abridged] We investigate the frequency of the various spectral types as a function both of the clusters properties and of the galaxies characteristics. In this way, using the same classification criteria adopted for higher redshift studies, we can consistently compare the properties of the local cluster population to those of their more distant counterparts. We describe a method we have developed to automatically measure the equivalent width of spectral lines in a robust way even in spectra with a non optimal signal to noise. Like this, we can derive a spectral classification reflecting the stellar content, based on the presence and strength of the [OII] and Hdelta lines. We are able to measure 4381 of the ~6000 originally observed spectra, in the fields of 48 clusters, 2744 of which are spectroscopically confirmed cluster members. The spectral classification is then analyzed as a function of galaxies luminosity, stellar mass, morphology, local density and host clusters global properties, and compared to higher redshift samples (MORPHS and EDisCS). The vast majority of galaxies in the local clusters population are passive objects, being also the most luminous and massive. At a magnitude limit of Mv<-18, galaxies in a post-starburst phase represent only ~11% of the cluster population and this fraction is reduced to ~5% at Mv<-19.5, which compares to the 18% at the same magnitude limit for high-z clusters. Normal star forming galaxies [e( c )] are proportionally more common in local clusters. The relative occurrence of post--starbursts suggests a very similar quenching efficiency in clusters at redshifts in the 0 to ~1 range. Furthermore, more important than the global environment, the local density seems to be the main driver of galaxy evolution in local clusters, at least with respect to their stellar populations content.
We present a multi-wavelength analysis of the galaxies in nine clusters selected from the WINGS dataset, examining how galaxy structure varies as a function of wavelength and environment using the state of the art software GALAPAGOSII. We simultaneou
We study the redshift evolution of the dynamical properties of ~180,000 massive galaxies from SDSS-III/BOSS combined with a local early-type galaxy sample from SDSS-II in the redshift range 0.1<z< 0.6. The typical stellar mass of this sample is Mstar
We simulate the formation of a low metallicity (0.01 Zsun) stellar cluster in a dwarf galaxy at redshift z~14. Beginning with cosmological initial conditions, the simulation utilizes adaptive mesh refinement and sink particles to follow the collapse
Aims. We present the results from a comprehensive spectroscopic survey of the WINGS (WIde-field Nearby Galaxy-cluster Survey) clusters, a program called WINGS-SPE. The WINGS-SPE sample consists of 48 clusters, 22 of which are in the southern sky and
The HRS is a complete volume-limited sample of nearby objects including Virgo cluster and isolated objects. Using a recent compilation of HI and CO data we study the effects of the cluster on the molecular gas content of spiral galaxies. We first ide