We present MUSE observations of the field of the quasar Q0152 - 020 whose spectrum shows a Lyman limit system ( LLS ) at redshift z _ { abs } = 0.38 , with a metallicity Z \gtrsim 0.06 Z _ { \odot } .
The low ionization metal lines associated with the LLS present two narrow distinct absorption components with a velocity separation of 26 km s ^ { -1 } .
We detect six galaxies within 600 km s ^ { -1 } from the absorption redshift ; their projected distances from the quasar sightline range from 60 to 200 kpc .
The optical spectra of five of these galaxies exhibit prominent nebular emission lines , from which we deduce extinction-corrected star formation rates in the range SFR = 0.06–1.3 M _ { \odot } yr ^ { -1 } , and metallicities between 0.2 Z _ { \odot } and Z _ { \odot } .
The sixth galaxy is only detected in the stellar continuum .
By combining our data with archival Keck/HIRES spectroscopy of the quasar and HST/WFPC2 imaging of the field , we can relate absorption line and galaxy kinematics ; we conclude that the LLS is most likely associated with the galaxy closest to the quasar sight-line ( galaxy ‘ ‘ a ’ ’ ) .
Our morphokinematic analysis of galaxy ‘ ‘ a ’ ’ combined with the absorption line kinematics supports the interpretation that one of the absorption components originates from an extension of the stellar disk of galaxy ‘ ‘ a ’ ’ , while the other component may arise in accreting gas in a warped disk with specific angular momentum \sim 3 times larger than the specific angular momentum of the galaxy halo .
Such warped disks are common features in hydrodynamical simulations of cold-flow accretion onto galaxies ; the data presented here provide observational evidence in favour of this scenario .