The atomic hydrogen content of galaxies as a function of group-centric radius

We apply a spectral stacking technique to Westerbork Synthesis Radio Telescope observations measure the neutral atomic hydrogen content (HI) of nearby galaxies in and around galaxy groups at $z < 0.11$. Our sample includes 577 optically-selected (120 isolated 457 satellites) covering stellar masses between 10$^{10}$ 10$^{11.5}$ M$_{\odot}$, cross-matched with Yang's group catalogue, angular redshift positions from Sloan Digital Sky Survey. find that satellites centres have lower HI fixed mass morphology (characterised by inverse concentration index) relative those larger radii. These trends persist for both high-mass ($M_{\rm halo} > 10^{13.5}h^{-1}$M$_{\odot}$) low-mass \leqslant groups, but disappear if we only consider members low local density ($\Sigma <$ 5 gal/Mpc$^{-2}$) environments. Similar are found specific star formation rate. Interestingly, radial decreasing group-centric radius extend beyond virial radius, as close lack compared located more than $\sim$3.0 $R_{180}$ away center their nearest group. also these late-type subsample obtain similar results. results suggest reservoir can be affected before become satellites, indicating existence pre-processing infalling galaxies.