Abstract

A tight correlation between nuclear millimeter and X-ray emission has recently been found in nearby (z < 0.01) and low-Eddington ratio (lambda(Edd) < 0.1) radio-quiet active galactic nuclei (AGNs), suggesting a common origin in the hot X-ray corona. We test this relation in nine more distant AGNs (z similar to 0.06-0.16) with higher bolometric luminosities ( log ( L- bol / erg s (- 1) ) = 45.3 -46.3), Eddington ratios (lambda(Edd) = 0.19-0.85), and X-ray bolometric corrections (kappa = 29-194), selected from the Burst Alert Telescope (BAT) survey. We obtained observations with Swift at 2-10 keV and quasi-simultaneous observations with the Atacama Large Millimeter/submillimeter Array at 100 GHz with high angular resolution (<0 . '' 14 arcsec). We find that these high-luminosity AGNs lie above the millimeter/X-ray correlation defined by lower-luminosity sources. A joint fit to both samples yields a second-degree polynomial with an intrinsic scatter of 0.32 dex. Furthermore, the millimeter emission correlates linearly with both the UV disk luminosity and L-bol, with intrinsic scatters of 0.45 and 0.35 dex, respectively. We propose that the deviation from the linear millimeter/X-ray relation arises from a two-component coronal electron population: thermal electrons that produce X-rays, but become less efficient at higher luminosities, and nonthermal electrons that produce millimeter emission and remain tied to L-bol. Additional millimeter emission from outflow-driven shocks may also contribute, though spectral energy distribution modeling and spectral index studies favor a coronal origin.