RESOLUTION AND KINEMATICS OF MOLECULAR GAS SURROUNDING THE CLOVERLEAFQUASAR AT Z=2.6 USING THE GRAVITATIONAL LENS

Gravitational lenses have long been advertised as primitive telescopes , capable of magnifying cosmologically distant sources. In this Letter we present new, 0.'' 9 resolution CO (7-6) observations of the z = 2. 56 Cloverleaf quasar (H1413+117) and spatially resolved images. By mod eling the gravitational lens, we infer a size scale of 0.'' 3 (similar to 1 kpc) for the molecular gas structure surrounding the quasar, and the gas has a kinematic structure roughly consistent with a rotating disk. The observed properties of the GO-emitting gas are similar to th e nuclear starburst complexes found in the infrared luminous galaxies in the local universe, and metal enrichment by vigorous star formation within this massive nuclear gas complex can explain the abundance of carbon and oxygen in the interstellar medium of this system observed w hen the universe was only a few billion years old. Obtaining correspon ding details in an unlensed object at similar distances would be well beyond the reach of current instruments, and this study highlights the less exploited yet powerful use of a gravitational lens as a natural telescope.