The chemodynamical signature of coherent metal-poor inflow and enriched recycled accretion in the cool circumgalactic medium

The azimuthal and kinematic structure of the CGM is often interpreted as planar accretion and bipolar outflows, yet direct metallicity evidence for this picture remains ambiguous. We combine cloud-by-cloud ionization modelling with galaxy rotation kinematics for 21 galaxies from the Multiphase Galaxy Haloes Survey to investigate how metallicity depends on azimuthal angle and angular momentum. We find that low-ionization clouds kinematically consistent with disc rotation have $\approx 0.5$ dex lower metallicity near the projected major axis ($\Phi \lt 30^\circ$) than at larger azimuthal angles. Major-axis clouds also exhibit higher $N({\rm{{\rm H}{\small I}}})$, higher density, and reduced non-thermal line broadening compared to clouds at larger azimuthal angles. In contrast, the higher-ionization phase shows no significant metallicity dependence on azimuthal angle and has lower column densities, lower densities, higher temperatures, and broader line widths than the co-rotating major-axis low-ionization clouds. These combined metallicity–kinematic–ionization signatures are consistent with dynamically cold, metal-poor inflow along the disc plane and enriched, more turbulent gas at larger azimuthal angles that likely traces angular-momentum-supported recycled accretion, embedded within a dynamically complex warmer phase. These results show that metallicity and angular momentum are jointly imprinted by the baryon cycle and are both required to uncover the physical origins of CGM gas.