Discordance of the unified scheme with observed properties of quasars and high-excitation galaxies in the 3CRR sample
Abstract
We examine the consistency of the unified scheme of Fanaroff-Riley type II radio galaxies and quasars with their observed number and size distributions in the 3CRR sample. We separate the low-excitation galaxies from the high-excitation ones, as the former might not harbor a quasar within and thus may not be partaking in the unified scheme models. In the updated 3CRR sample, at low redshifts (z < 0.5), the relative number and luminosity distributions of high-excitation galaxies and quasars roughly match the expectations from the orientation-based unified scheme model. However, a foreshortening in the observed sizes of quasars, which is a must in the orientation-based model, is not seen with respect to radio galaxies even when the low-excitation galaxies are excluded. This dashes the hope that the unified scheme might still work if one includes only the high-excitation galaxies.
- Authors:
- Astronomy and Astrophysics Division, Physical Research Laboratory, Navrangpura, Ahmedabad 380 009 (India)
- Publication Date:
- OSTI Identifier:
- 22342301
- Resource Type:
- Journal Article
- Journal Name:
- Astronomical Journal (New York, N.Y. Online)
- Additional Journal Information:
- Journal Volume: 148; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1538-3881
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; DISTRIBUTION; EXCITATION; GALAXY NUCLEI; LUMINOSITY; ORIENTATION; QUASARS; RADIO GALAXIES; RED SHIFT
Citation Formats
Singal, Ashok K., E-mail: asingal@prl.res.in. Discordance of the unified scheme with observed properties of quasars and high-excitation galaxies in the 3CRR sample. United States: N. p., 2014.
Web. doi:10.1088/0004-6256/148/1/16.
Singal, Ashok K., E-mail: asingal@prl.res.in. Discordance of the unified scheme with observed properties of quasars and high-excitation galaxies in the 3CRR sample. United States. https://doi.org/10.1088/0004-6256/148/1/16
Singal, Ashok K., E-mail: asingal@prl.res.in. 2014.
"Discordance of the unified scheme with observed properties of quasars and high-excitation galaxies in the 3CRR sample". United States. https://doi.org/10.1088/0004-6256/148/1/16.
@article{osti_22342301,
title = {Discordance of the unified scheme with observed properties of quasars and high-excitation galaxies in the 3CRR sample},
author = {Singal, Ashok K., E-mail: asingal@prl.res.in},
abstractNote = {We examine the consistency of the unified scheme of Fanaroff-Riley type II radio galaxies and quasars with their observed number and size distributions in the 3CRR sample. We separate the low-excitation galaxies from the high-excitation ones, as the former might not harbor a quasar within and thus may not be partaking in the unified scheme models. In the updated 3CRR sample, at low redshifts (z < 0.5), the relative number and luminosity distributions of high-excitation galaxies and quasars roughly match the expectations from the orientation-based unified scheme model. However, a foreshortening in the observed sizes of quasars, which is a must in the orientation-based model, is not seen with respect to radio galaxies even when the low-excitation galaxies are excluded. This dashes the hope that the unified scheme might still work if one includes only the high-excitation galaxies.},
doi = {10.1088/0004-6256/148/1/16},
url = {https://www.osti.gov/biblio/22342301},
journal = {Astronomical Journal (New York, N.Y. Online)},
issn = {1538-3881},
number = 1,
volume = 148,
place = {United States},
year = {Tue Jul 01 00:00:00 EDT 2014},
month = {Tue Jul 01 00:00:00 EDT 2014}
}