DAMPED LYMAN-ALPHA ABSORPTION IN Q0957+561A,B

A series of archival IUE low-dispersion spectral observations of the double quasar Q0957 + 561A, B are analyzed. The components of this gravitationally lensed quasar are separated by approximately 6''. Damped Lyalpha absorption at redshift z(abs) = 1.3911 with neutral hydrogen column density N(H I) congruent-to 7 x 10(19) cm-2 is present in the spectra of both the A and B components. Using an accepted model by Young et al. for the gravitational lens, the damped Lyalpha absorber is inferred to have a minimum size of approximately 0.5h(50)-1 kpc. The standard interpretation is that a damped Lyalpha absorber represents a galactic or protogalactic H I disk. In the context of this standard model, the absorption-line properties and evidence for Faraday rotation are discussed.