1998/04/21 by Jean‐Paul Kneib, J. -P. Kneib, D. Alloin +5
Engineering · Physics and Astronomy · #Adaptive optics and wavefront sensing #Astronomy and Astrophysical Research #Astrophysics (astro-ph) #Calibration and Measurement Techniques #FOS: Physical sciences #Spacecraft and Cryogenic Technologies #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/9804207
Submitted to A&A letters
arxiv created 1998/04/21 · openalex publication_date 1998/04/21 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We present new elements in the identification of the lens-system producing\nthe 4 images of the BAL quasar H1413+117, based on the recent\nHST/NICMOS-2/F160W observations. After a careful PSF subtraction of the 4\nimages of the quasar, the residual H image reveals the presence of a faint\nobject (H~20.5) within the region enclosed by the 4 quasar images. This object\ncorresponds to a single galaxy: the primary lens of the lens-system. We also\nidentify the galaxies around the Cloverleaf which had been proposed to belong\nto a galaxy cluster/group at high redshift (Kneib et al 1998): the other\ncomponent in the lens-system that provides the additional "external" shear. For\nthese galaxies, we have derived a likely redshift based upon their R, I and H\nmagnitudes. We find that most of them are consistent with belonging to a galaxy\ncluster/group with mean redshift <z>=0.9 +/- 0.1. Furthermore we detect 2 very\nred objects (I-H~4): the faintest one has no observed optical (R and I)\ncounterpart, while the brightest has a predicted redshift around z~2, and may\nbe identified with one of the Cloverleaf absorbers. This gravitational-lens\nsystem constitutes an excellent target for IR imaging/spectroscopy with the new\ngeneration of 8m ground-based telescopes.\n