LBQS 1429-0053: a binary quasar rather than a lensed quasar
Abstract
Very deep ESO/VLT FORS1 and ISAAC images, as well as HST NICMOS2 data are used to infer the nature of the quasar pair LBQS 1429-0053 A and B, either a binary quasar or a doubly-imaged lensed quasar. Direct search of a putative lensing galaxy is unsuccessful . Moreover, no galaxy overdensity close to the quasar pair is found. A weak shear analysis of the field also fails at detecting any concentration of dark matter and weakens the hypothesis of a dark lens. The only sign of a possible lens consists in a group of 5 objects at z~1, within a radius of 5'', from the quasar pair. Considering this group as the lensing potential does not allow to reproduce the image position and flux ratio of the quasars. Our deep R-band image shows a blue, extended object at the position of quasar A, which is consistent with either being the lensed quasar A host, or being an intervening galaxy at lower redshift. Unless future very deep optical images demonstrate that this object is actually the lensed host of LBQS 1429-0053, we conclude that there is very little evidence for this quasar being lensed. Therefore, we are led to declare LBQS 1429-0053 A and B a genuine binary quasar.
Cite
@article{arxiv.astro-ph/0303589,
title = {LBQS 1429-0053: a binary quasar rather than a lensed quasar},
author = {C. Faure and D. Alloin and S. Gras and F. Courbin and J. -P. Kneib and P. Hudelot},
journal= {arXiv preprint arXiv:astro-ph/0303589},
year = {2009}
}
Comments
9 pages, 6 jpg images, accepted for publication in A&A