An ALMA View of the Host Galaxies of Radio-Loud Quasars at z>5

The last few years have seen a true Golden Age for the discovery and characterization of luminous quasars at the highest redshifts (z>5, within 1Gyr from the Big Bang, i.e. in the Epoch of Reionization); ~10% of such quasars are classified as radio-loud, i.e. they show powerful radio-jets. The interaction between these jets and the interstellar medium in their host galaxies is thought to play a crucial role in the supermassive black hole/galaxy (co-)evolution. However, very little have been known so far about this interaction at high-z, due to the lack of (sub)-mm observations of such radio-loud quasars.
Here, we present new ALMA observations of the host galaxies of six radio-loud quasars at z>5, aimed at recovering their dust emission and their [CII] emission line in the rest-frame far-infrared. We show that these galaxies already host large dust reservoirs and are forming stars at rates>~30 Msun/yrs. We compare their far-infrared and [CII] emission line properties with those of radio-quiet quasars at comparable redshifts, in order to highlight any potential star formation enhancement/suppression from the radio jets. Lastly, we search for potential gas-rich galaxies surrounding these radio-loud quasars, as expected from theoretical predictions.