CO Survey of High-z Radio Galaxies, Revisited with the Atacama Large Millimeter/submillimeter Array: Jet–Cloud Alignments and Synchrotron Brightening by Molecular Gas in the Circumgalactic Environment

Abstract Powerful radio sources associated with supermassive black holes are among the most luminous objects in universe, and frequently recognized both as cosmological probes active constituents evolution of galaxies. We present alignments between jets cold molecular gas environment distant galaxies, show that brightness synchrotron source can be enhanced by its interplay gas. Our work is based on CO J > 1 observations Atacama Large Millimeter/submillimeter Array (ALMA) three galaxies redshifts range 1.4 < z 2.1, namely MRC 0114-211 ( = 1.41), 0156-252 2.02), 2048-272 2.05). These ALMA support previous found out to 50 kpc circumgalactic environment, a CO(1–0) survey performed Australia Telescope Compact Array. The emission along axes but beyond main lobes. When compared large sample high- from literature, we find presence this medium correlates an increased flux-density ratio versus counter-lobe. This suggest lobe brightens when encountering environment. While part likely related interstellar either host or companion galaxy, significant fraction these systems shows very low excitation, r 2−1/1−0 3−2/1−0 values ≲0.2. could medium.