A Systematic Method for Identifying Absorption Lines as Applied to PKS 0237-23
Abstract
A systematic method for identifying the absorption lines in quasi-stellar sources with rich absorption spectra is described, and the lines that are expected on theoretical grounds to have the highest probability of appearing in absorption in quasi-stellar sources are listed. The computational scheme that was devel- oped for recognizing and analyzing candidate redshifts is then described; this computationa' scheme is supplemented by a set of rules used to determine if a candidate redshift is acceptable The computational scheme and formal rules were applied to a set of nonsense spectra, i.e, random-number spectra, with the same main characteristics as the absorption spectrum of PKS 0237-23 determined by Greenstein and Sargent The average number of acceptable redshifts per nonsense spectrum was 0.7. Five acceptable redshifts were found in the real spectrum: z = 2 2015, 1.671, 1 656, 1.513, and 1.364 No acceptable redshift was found at z = 1 95. A list of additional lines that should be detectable if the identifications proposed here are correct is given for slightly longer and shorter wavelengths than covered in the observa- tions of Greenstein and Sargent Some characteristics of the identifications are also described
- Publication:
-
The Astrophysical Journal
- Pub Date:
- August 1968
- DOI:
- 10.1086/149695
- Bibcode:
- 1968ApJ...153..679B