Spectroscopy of the Gravitational Arcs in CL 2244-02, A370 (Arclet A5), and CL 0024+1654
Abstract
We analyze new spectroscopic data on the blue giant arc in Cl 2244 - 02, on the arclet A5 in Abell 370, and on the split arc in Cl 0024+1654. A probable redshift z = 2.237 is derived for the source of the Cl 2244-02 arc, making this object one of the most distant "field" galaxies known today. A star formation rate is estimated from the Lyα intensity and compared to other distant field galaxies. For A5, no prominent emission line is found, but three absorption lines point to a tentative redshift z = 1.306. The spectra of the four parts of the Cl 0024+1654 arc look rather similar, but the absence of any spectral feature allows only the determination of a redshift range: 1 <z <2.1. The systematic search for such arcs and/or arclets, and the Toulouse spectroscopic survey of arcs which follows up, seems one of the promising methods of obtaining spectra of extremely distant field galaxies and of constraining their early evolution.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- October 1991
- DOI:
- 10.1086/170592
- Bibcode:
- 1991ApJ...380..334M
- Keywords:
-
- Astronomical Spectroscopy;
- Galactic Clusters;
- Galactic Evolution;
- Gravitational Effects;
- Absorption Spectra;
- Arcs;
- Emission Spectra;
- Lyman Alpha Radiation;
- Red Shift;
- Star Formation Rate;
- Astrophysics;
- GALAXIES: CLUSTERING;
- GALAXIES: REDSHIFTS;
- GRAVITATIONAL LENSES