X-RAY PROPERTIES OF ISOLATED EARLY-TYPE GALAXIES

We plan to derive the Xray properties of 3 isolated early type galaxies toprovide answers to fundamental issues concerning the connection betweenenvironment and E galaxies formation. The Xray data will tell us whether groupdominant Es are indeed overluminous and significantly more extended relative toisolated ones. While the presence of extended halos provides strongobservational support to theories assuming that bright Es are formed withingroups, non detections might severely challenge these hierarchical formationmodels. Isolated E samples used in previous works include non isolated Es, dueto limitations in the parent sample from which they are drawn. We therefore haveselected a new sample with solid isolation criteria. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]