Clustercentric-radius dependence of gas fraction as shown in the phase-space diagram (left panel) and gas fraction vs. ﹩{k}_{b}=(| {\rm{\Delta }}v| /{\sigma }_{\mathrm{cluster}})\times (R/{R}_{200{\rm{c}}})﹩ plane, which is a proxy for clustercentric radius in 3D (right panel). Galaxies are color-coded by their gas fraction normalized by the value of field galaxies at the same ΔMS, mass, and redshifts (Tacconi et al. 2018). Curves of constant k_b values with ﹩{k}_{b}=0.05,0.2,0.64﹩ are shown in the left panel. A strong clustercentric radius dependence of gas content is revealed, with decreasing gas fraction for galaxies closer to the cluster center, which is true for either absolute or normalized value of gas fraction.