A search for the optical counterpart of the Einstein ring PKS 1830-211

We report the results of deep optical and IR imaging, astrometry, and spectroscopy of the recently identified Einstein ring source PKS 1830-211. (Rao & Subrahmanyan 1988, Swarup et al. 1989, Subrahmanyan et al. 1990). We made several attempts to secure an optical or IR ID of this object, using observations from Palomar and ESO, May 1988 – May 1990. Several objects are visible within the 2-σ error circle in our CCD images, including the ≈ 22^m object (which may be extended, or a close double) proposed as the tentative counterpart by Subrahmanyan et al. 1990. This, and another object ≈ 1.2″ NE from it may represent the optical counterparts of the two major radio source components. We cannot yet unambiguously determine which one(s), if any, of these objects represent the correct ID. The lensing galaxy is likely to be at a redshift of at least a few tenths. A full account of this work will be submitted for publication shortly. Some of the data used here were obtained as a part of the ESO Key Project on Gravitational Lenses. S.D. acknowledges a partial support from the Alfred P. Sloan Foundation, and the NSF PYI award AST-9157412.