A search for clusters and groups of galaxies on the line of sight towards 8 lensed quasars
نویسندگان
چکیده
In this paper we present new ESO/VLT FORS1 and ISAAC images of the fields around eight gravi-When available and deep enough, HST/WFPC2 data were also used to infer the photometric redshifts of the galaxies around the quasars. The search of galaxy overdensities in space and redshift, as well as a weak-shear analysis and a mass reconstruction are presented in this paper. We find that there are most probably galaxy groups towards CTQ 414, HE 0230-2130, B 1359+154, H 1413+117 and HE 2149-2745, with a mass ≤4 10 14 M⊙h −1. Considering its photometric redshift, the galaxy group discovered in the field around HE 1104-1805 is associated with the quasar rather than with the lensing potential.
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