Evidence for a population of beamed radio intermediate quasars
Abstract
Whether radio intermediate quasars possess relativistic jets as radio-loud quasars is an important issue in the understanding of the origin of radio emission in quasars. In this letter, using the two-epoch radio data obtained during Faint Image of Radio Sky at Twenty centimeter sky (FIRST) and NOAO VLA Sky Survey (NVSS), we identify 89 radio variable sources in the Sloan Digital Sky Survey. Among them, more than half are radio intermediate quasars (RL=f2cm/f2500A<250). For all objects with available multiple band radio observations, the radio spectra are either flat or inverted. The brightness temperature inferred from the variability is larger than the synchrotron-self Compton limit for a stationary source in 87 objects, indicating of relativistic beaming. Considering the sample selection and viewing angle effect, we conclude that relativistic jets probably exist in a substantianl fraction of radio intermediate quasars.
Keywords
Cite
@article{arxiv.astro-ph/0603513,
title = {Evidence for a population of beamed radio intermediate quasars},
author = {Tinggui Wang and Hongyan Zhou and Junxian Wang and Youjun Lu and Yu Lu},
journal= {arXiv preprint arXiv:astro-ph/0603513},
year = {2009}
}
Comments
15 pages, 4 figures, 1 table, Accepted to the Astrophysical Journal