Inthe framework of the single-particle potential model, the root-meamsquare radii of s-wave valence proton distributions for P and S isotopes have been systematically calculated. The scaling law of s-wave valence proton distributions is obtained by analyzing the relation between radii and separation energies. Necessary condition for the occurrence of 2sl/2-state proton halos is deduced from the scaling law. Quantitative condition derived from this work can to some extent serve as reference for proton halo search.
With the experimental binding energies and configurations, the root-mean-square radii of p-wave valence neutron distributions for nuclei up to the second p-shell have been calculated in the framework of the single-particle potential model. By analyzing the relations between the radii and the binding energies, the scaling laws of p-wave valence neutron distributions are obtained. The quantitative conditions for the formation of p-wave neutron halos are deduced from these scaling laws. Based on the investigation on the probability of finding the valence nucleon outside the range of the interaction potential, a 2p3/2 halo state in 47S is anticipated for the first time. These obtained results might provide reference for searching for p-wave neutron halos in nuclei up to the second p-shell.