December 9, 1999 Pratt Conference Room, Perkin G-04, 12:30 pm
Weak lensing study of low mass groups: implications for Omega_m
Dr. Henk Hoekstra, University of Gronigen
Groups of galaxies are the most common structures in the universe. Only
recently it has become possible to identify a large number of such systems
at intermediate redshifts thanks to the CNOC2 field galaxy redshift survey.
We have measured for the first time the weak lensing signal induced by
galaxy groups, and have obtained estimates for their average mass and
mass-to-light ratio, leading to a new estimate for the density of the
universe.