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A search for clusters and groups of galaxies on the line of sight towards 8 lensed quasars

C. Faure·D. Alloin·J. -P. Kneib·F. Courbin
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Abstract

In this paper we present new ESO/VLT FORS1 and ISAAC images of the fields around eight gravitationally lensed quasars: CTQ414, HE0230-2130, LBQS1009-0252, B1030+074, HE1104-1805, B1359+154, H1413+117 and HE2149-2745. 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 CTQ414, HE0230-2130, B1359+154, H1413+117 and HE2149-2745, with a mass ~ 4x10^14 M_sol h^-1. Considering its photometric redshift, the galaxy group discovered in the field around HE1104-1805 is associated with the quasar rather than with the lensing potential.

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C. Faure, D. Alloin, J. -P. Kneib, F. Courbin. 2004-05-26. A search for clusters and groups of galaxies on the line of sight towards 8 lensed quasars. https://doi.org/10.1051/0004-6361%3A20040406

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