Magellan Spectroscopy of the Galaxy Cluster RX J1347.5-1145: Redshift Estimates for the Gravitationally Lensed Arcs
Abstract
We present imaging and spectroscopic observations of the gravitationally lensed arcs in the field of RX J1347.5-1145, the most X-ray luminous galaxy cluster known. Based on the detection of the [O II] λ3727 emission line, we confirm that the redshift of one of the arcs is z=0.806. Its color and [O II] line strength are consistent with those of distant, actively star-forming galaxies. In a second arc, we tentatively identify a pair of absorption lines superposed on a red continuum; the lines are consistent with Ca II λ3933 (K) and Ca II λ3968 (H) at z=0.785. We detected a faint blue continuum in two additional arcs, but no spectral line features could be measured. We establish lower limits to their redshifts based on the absence of [O II] emission, which we argue should be present and detectable in these objects. Redshifts are also given for a number of galaxies in the field of the cluster.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- September 2002
- DOI:
- 10.1086/342124
- arXiv:
- arXiv:astro-ph/0206424
- Bibcode:
- 2002ApJ...577..133R
- Keywords:
-
- Galaxies: Clusters: Individual: Alphanumeric: RX J1347.5-1145;
- Galaxies: Distances and Redshifts;
- Cosmology: Gravitational Lensing;
- Astrophysics
- E-Print:
- To appear in The Astrophysical Journal (September 2002). 6 pages