A Lensed Arc in the Low Redshift Cluster Abell 2124
Abstract
We report the discovery of an arc-like object 27" from the center of the cD galaxy in the redshift cluster A2124. Observations with the Keck II telescope reveal that the object is a background galaxy at , apparently lensed into an arc of length \sim 8 \farcs5 and total R magnitude . The width of the arc is resolved; we estimate it to be 0\farcs6 after correcting for seeing. A lens model of the A2124 core mass distribution consistent with the cluster galaxy velocity dispersion reproduces the observed arc geometry and indicates a magnification factor 9. With this magnification, the strength of the [OII] \lambda 3727 line implies a star-formation rate of SFR \sim 0.4 h^{-2}\msun yr^{-1}$. A2124 thus appears to be the lowest redshift cluster known to exhibit strong lensing of a distant background galaxy.
Cite
@article{arxiv.astro-ph/9809078,
title = {A Lensed Arc in the Low Redshift Cluster Abell 2124},
author = {John P. Blakeslee and Mark R. Metzger},
journal= {arXiv preprint arXiv:astro-ph/9809078},
year = {2009}
}
Comments
6 pages using emulateapj.sty; 4 Postscript figures; Figure 4 uses color. Accepted for publication, but ApJ Letters' new policy of counting data images makes the manuscript too long; will appear in main journal. This final version has minor corrections