DETECTION OF FAR-ULTRAVIOLET HIGH-EXCITATION LINE EMISSION AND LYMAN-BETA ABSORPTION IN THE GRAVITATIONAL LENS Q0957+561

Test runs with a new data processing software system on archival spectra obtained by the International Ultraviolet Explorer (IUE) reveal high-excitation emission lines in the gravitationally lensed binary quasar 0957+561. The lines of O VI lambdalambda1031,1037 and S VI lambdalambda933,945 are readily seen in a single 390 minute, low-dispersion IUE exposure, when calibrated with the New Spectral Image Processing System (NEWSIPS). Co-addition of 10 exposures, as processed by NEWSIPS, followed by the application of a five-point smoothing filter, allows clear detection of the additional emission of C III lambda978, N III lambda992, S IV lambdalambda1063-1073, N II lambda1084, Fe in (UVI; lambda1125), and N V lambda1238. These identifications assume rest wavelengths consistent with the z = 1.41 redshift of the lensed quasar. In addition, we find a strong absorption that can be attributed to H I Lyman-beta lambda1017 with a redshift consistent with a previously reported damped Lyman-alpha absorption system at z = 1.3911, which is probably associated with intervening gas near the quasar (Turnshek & Bohlin 1993). Another absorption feature appears to be due to Si II lambdalambda 1190,1193 in the halo of an intervening galaxy at z = 1.38. Finally, the strong discontinuity in the continuum at the Lyman limit lambda912 is appropriate to absorption that corresponds to the Lyman-alpha and, Lyman-beta absorption line system at Z = 1.3911. These first results suggest that NEWSIPS is capable of disclosing much previously unrecognized information that is contained in the nearly 100,000 ultraviolet spectra currently in the IUE Archive, especially in regions of the spectra that are under-exposed.