Improved lower limits on Lyman-alpha forest cloud dimensions and additional evidence supporting the gravitational lens nature of 2345+007 A, B.
Abstract
Spectra have been obtained of the QSO pair 2345 + 007A,B previously reported as a gravitational lens candidate. These new observations strongly support the interpretation of the pair as a gravitationally split image. In addition, several Ly-alpha absorption-line systems are found in common between the two images, yielding a new lower limit of the order of 5-25 kpc for the characteristic size of the Ly-alpha clouds at redshift z = 2. There appear to be two or three lines which are not in common or are of substantially different strengths, so that this scale may be a rough characteristic size rather than a lower limit. One metal-line system is also found in common, which exhibits a marked difference between the two QSO images in the low-ionization component.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- June 1984
- DOI:
- 10.1086/184271
- Bibcode:
- 1984ApJ...281L...1F
- Keywords:
-
- Astronomical Spectroscopy;
- Gravitational Lenses;
- Lyman Alpha Radiation;
- Quasars;
- Absorption Spectra;
- Red Shift;
- Astrophysics