The redshifts of the gravitational lens galaxies in MG1131+0456 and B1938+666 are 0.844 and 0.878 respectively. Both are early-type galaxies lying at the redshifts predicted by assuming that they are early-type galaxies with old stellar populations lying on the fundamental plane. We also find evidence for a foreground group of galaxies at z=0.343 near MG1131+0456. The source redshifts are predicted to be >1.8 in both systems, but they are so red that infrared spectra will be required to determine their redshifts.
Tonry et al. (Wed,) studied this question.
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