An extended [C <scp>ii</scp>] halo around a massive star-forming galaxy at <i>z</i> = 5.3

ABSTRACT High-redshift observations are often biased towards massive and bright galaxies that not necessarily representative of the full population. In order to accurately study galaxy evolution mass assembly at these redshifts, ‘normal’ main sequence required. Here we present Atacama Large Millimeter/Submillimeter Array (ALMA) 0.3 arcsec resolution [C ii] emission line 158 μm HZ7, a z = 5.25. Comparing archival rest-frame UV taken by Hubble Space Telescope (HST), find strong evidence existence extended emission, which estimate be twice size yielding one first high-redshift objects where clear signature ‘Halo’ has been detected date. For matched Sérsic profile with n 1, measured effective radius 0.50 ± 0.04 (3.07 0.25 kpc) an average 0.2 (1.48 0.16 kpc). The morphology kinematics system suggest merging event resulting in non-rotating disc system. This could responsible for [CII] emission. Alternatively, some potential obscured also explain ratio. These results contribute growing consensus respect around galaxies.