mm-wave emission from Active Galactic Nuclei (AGN) may hold the key to understanding the physical origin of their radio cores. The correlation between radio/mm and X-ray luminosity may suggest a similar physical origin of the two sources. Since synchrotron self absorption decreases with frequency, mm-waves probe smaller length scales than cm-waves. We report on 100 GHz (3 mm) observations with CARMA of 26 AGNs selected from the hard X-ray Swift/BAT survey. 20/26 targets were detected at 100 GHz down to the 1 mJy (3 σ) sensitivity, which corresponds to optically thick synchrotron source sizes of 10−4 - 10−3 pc). Most sources show a 100 GHz flux excess with respect to the spectral slope extrapolated from low frequencies. This mm spectral component likely originates from smaller scales than the few-GHz emission. The measured mm sources lie roughly around the Lmm (100 GHz) ∼ 10−1 LX (2-10 keV) relation, similar to a few previously published X-ray selected sources, and hinting perhaps at a common coronal origin.
@article{arxiv.1803.06877,
title = {The mm-wave compact component of AGN},
author = {Ehud Behar and Stuart Vogel and Ranieri D. Baldi and Krista L. Smith and Richard F. Mushotzky},
journal= {arXiv preprint arXiv:1803.06877},
year = {2018}
}
Comments
submitted to MNRAS, revised by the referee, comments welcome (9 pages, 4 figures)