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Polar Outflows in Six Broad Absorption Line Quasars

Hongyan Zhou·Tinggui Wang·Huiyuan Wang·Junxian Wang·Weimin Yuan·Yu Lu
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Abstract

Using the radio observations by FIRST and NVSS, we build a sample of 151 radio variable quasars selected from the Sloan Digital Sky Survey Data Release 3 (SDSS DR3). Six (probably another two) among them are classified as broad absorption line (BAL) quasars, with radio flux variations of a few 10 percent within 1.5-5 years. Such large amplitudes of the variations imply brightness temperatures much higher than the inverse Compton limits (10$^{12}$ K) in all the BAL quasars, suggesting the presence of relativistic jets beaming toward the observer. The angle between the outflow and the jet is constrained to be less than $\sim 20^{\circ}$. Such BAL quasars with polar outflows are beyond the simple unification models of BAL quasars and non-BAL quasars, which hypothesize that BAL quasars are normal quasars seen nearly edge-on.

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Hongyan Zhou, Tinggui Wang, Huiyuan Wang, Junxian Wang, Weimin Yuan, Yu Lu. 2005-10-08. Polar Outflows in Six Broad Absorption Line Quasars. https://doi.org/10.1086/499768

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