X-RAY-ABSORPTION TOWARD THE EINSTEIN RING SOURCE PKS-1830-211

PKS 1830-211 is an unusually radio-loud gravitationally lensed quasar. In the radio spectrum, the system appears as two compact, dominant fe atures surrounded by relatively extended radio emission that forms an Einstein ring. As the line of sight to it passes close to our Galactic center, PKS 1830-211 has not been detected in wave bands other than t he radio and X-ray so far. Here we present X-ray data of PKS 1830-211 observed with ROSAT Position Sensitive Proportional Counter. The X-ray spectrum shows that absorption in excess of the Galactic contribution is highly likely, which at the redshift of the lensing galaxy (z(l) = 0.886) corresponds to N-H = 3.5(-0.5)(+0.6) x 10(22) atoms cm(-2). Th e effective optical extinction is large, A(V)(observed) greater than o r similar to 5.8. When corrected for this additional extinction, the t wo-point optical to X-ray slope alpha(ox) of PKS 1830-211 lies just wi thin the observed range of quasars. It is argued here that both compac t images must be covered by the X-ray absorber(s) that we infer to be the lensing galaxy (galaxies). The dust-to-gas ratio along the line of sight within the lensing galaxy is likely to be somewhat larger than for our Galaxy.