The first joint ALMA/X-ray monitoring of a RQ AGN: understanding the origin of the compact mm emission

The origin of compact radio/mm emission observed in nearly all radio-quiet Active Galactic Nuclei (AGN) is still debated. Recent studies have proposed that it is produced by self-absorbed synchrotron emission from the accretion disk corona, which is also responsible for the X-ray emission ubiquitously observed in AGN. The detection of correlated variability between the mm and X-ray bands would be the smoking gun supporting this idea. We carried out the first joint mm (ALMA; ∼100 GHz)/X-ray (NICER/NuSTAR/XMM-Newton/Swift; 0.3-10 keV) observations of the brightest unobscured radio quiet-AGN, IC 4329A (z = 0.016). In my talk, I will present the first results of this large campaign, discussing the relation between the X-ray corona and the compact radio emission observed in radio-quiet AGN.