Evolutionary behaviour of BL Lac objects
Astrophysics
2007-05-23 v1
Abstract
We present analysis of a new flux limited sample of 72 X-ray selected BL Lacertae objects with known redshifts for 59 of them. We find the more X-ray dominated BL Lac having negative evolution with redshift, while intermediate objects show no evolution at all. X-ray dominated objects show higher X-ray luminosities and flatter X-ray spectra than the intermediate ones. We were also able to determine the redshift of 1517+656, which is part of our sample and is the optically most luminous X-ray selected BL Lac known so far.
Cite
@article{arxiv.astro-ph/9810154,
title = {Evolutionary behaviour of BL Lac objects},
author = {Volker Beckmann},
journal= {arXiv preprint arXiv:astro-ph/9810154},
year = {2007}
}
Comments
12 pages, 6 Postscript figures, to appear in the proceedings of the conference "BL Lac Phenomenon" held in Turku, Finland, June 22-26, 1998