SDSS J115517.35+634622.0: A Newly Discovered Gravitationally Lensed Quasar

Research paper by Bart Pindor, Daniel J. Eisenstein, Naohisa Inada, Michael D. Gregg, Robert H. Becker, Jon Brinkmann, Scott Burles, Joshua A. Frieman, David E. Johnston, Gordon T. Richards, Donald P. Schneider, Ryan Scraton, Maki Sekiguchi, Edwin L. Turner, Donald G. York

Indexed on: 05 Dec '03Published on: 05 Dec '03Published in: Astrophysics

Abstract

We report the discovery of SDSSJ115517.35+634622.0, a previously unknown gravitationally lensed quasar. The lens system exhibits two images of a $z = 2.89$ quasar, with an image separation of $1{\farcs}832 \pm 0.007$ . Near-IR imaging of the system reveals the presence of the lensing galaxy between the two quasar images. Based on absorption features seen in the Sloan Digital Sky Survey (SDSS) spectrum, we determine a lens galaxy redshift of $z = 0.1756$. The lens is rather unusual in that one of the quasar images is only $0{\farcs}22\pm0{\farcs}07$ ($\sim 0.1 R_{\rm eff}$) from the center of the lens galaxy and photometric modeling indicates that this image is significantly brighter than predicted by a SIS model. This system was discovered in the course of an ongoing search for strongly lensed quasars in the dataset from the SDSS.