Περίληψη :
Much of the evolution of galaxies takes place in groups where feedback has the greatest impact on galaxy formation. By using an optically selected, statistically complete sample of 53 nearby groups (<80 Mpc; CLoGS sample), observed at both radio (GMRT) and X-ray (Chandra and XMM-Newton) frequencies, my work aims to characterize the radio-AGN population in groups and examine their impact on the intra-group gas and member galaxies. In this talk, I will present results from the study of the 26 central brightest group early-types (BGEs) from the high richness CLoGS sub-sample. Using the sensitivity to older electron populations at 235 MHz and the resolution at 610 MHz as a key to identify past and current AGN activity, I will discuss the radio properties (morphology, spectral index) that central group radio sources present in our sample, along with information on the energetics and the group environment that they lie into, in combination with findings from the X-ray observations. I will conclude the talk with the latest results obtained in the BGEs using multiple wavelengths (GALEX FUV, K band) that are crucial in examining the evolution of galaxy groups.
