CTQ 414: a new gravitational lens

Abstract

We report the discovery and ground-based observations of the new gravitational lens CTQ 414. The source quasar lies at a redshift of z\1.29 with a B magnitude of 17.6. Ground-based optical imaging reveals two point sources separated by 1A.2 with a magnitude di erence of roughly 1 mag. Subtraction of two stellar point-spread functions from images obtained in subarcsecond seeing consistently leaves behind a faint, residual object. Fits for two point sources plus an extended object places the fainter object collinear with the two brighter components. Subsequent Hubble Space Telescope Near Infrared Camera and Multi-Object Spectrometer (NICMOS) observations have conÐrmed the identiÐcation of the fainter object as the lensing galaxy. Very Large Array observations at 8.46 GHz reveal that all components of the lensing system are radio-quiet down to the 0.2 mJy Ñux level.