The Detection of the λ2175 Feature and Further Analysis of the Broad Absorption Line Profile Structure in the Gravitational Lens Candidate UM 425

摘要

We obtained Multiple Mirror Telescope spectra of the gravitational lens candidate UM 425 to compare the redshifts and line profile structures of lens components A and B, which are separated by approximately 6".5. The C IV λ1550 emission in both A and B exhibits broad absorption line (BAL) structure, consistent with the earlier detection of BAL structure in O VI λ1033 and N V λ1240 that was found with the International Ultraviolet Explorer in component A. Cross-correlation of the spectra of A and B using emission lines of C IV λ1550, He II λ1640, N III λ1750, C III] λ1909, and Mg II λ2800 reveals a difference in the redshifts of A and B. However, the detailed BAL profile structure found in the spectra of A and B are strikingly similar to one another, which suggests the system is lensed.