Redshifts of the Gravitational Lenses MG0414+0534 and MG0751+2716
Abstract
We report redshifts in two gravitational lens systems, MG0414+0534 and MG0751+2716. The lens galaxy in MG0414+0534 lies at zl=0.9584+/-0.0002. The luminosity and extreme red color of the lens are then typical of a passively evolving, early-type, ~2L* galaxy. The galaxy cannot have a significant global mean extinction without being anomalously luminous. The lens galaxy in MG0751+2716 has a redshift of zl=0.3502+/-0.0003 and it is a member of a small group. The group includes the nearby, bright companion galaxy whose redshift we confirmed to be z=0.3501+/-0.0001 and a nearby emission line galaxy with z=0.3505+/-0.0003. A second emission line galaxy with z=0.5216+/-0.0001 was found nearly superposed on the first emission line galaxy. The source in MG0751+2716 is a zs=3.200+/-0.001 radio quasar. For flat universes with Omega0=1.0 (0.3), 96% (87%) of lenses like MG0414+0534 and 7% (3%) of lenses like MG0751+2716 are expected to have lower lens redshifts than observed.
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