Skin values and matter radii of 208Pb and 58,60,64Ni based on reaction cross section of 3,4He scattering

Abstract

Background:The PREX group reported a new skin value, rskin208(PREX2)=0.283±0.071=0.212∼0.354fm. Using the chiral (Kyushu) g-matrix folding model with the proton and neutron densities determined with D1S+GHFB+AMP, we determined neutron skin thickness rskin208(exp)=0.278±0.035 fm from reaction cross sections σR(exp) of p+208Pb scattering, where D1S-GHFB+AMP denotes Gogny-D1S HFB with angular momentum projection (AMP). The method also yielded rskin208(exp)=0.416±0.146 from σR(exp) of 4He+208Pb scattering. In our previous work, we accumulated the 206 EoSs and determined a sloop parameter L=76∼165MeV from the 206 EoSs. The value of L yields rskin208=0.102∼0.354fm. As for 58Ni, a novel method for measuring nuclear reactions in inverse kinematics with stored ion beams was successfully used to extract matter radii rm of 58Ni at the GSI facility. Purpose:As the first aim, we first determine rskin208(exp) from σR(exp) of 3He scattering on 208Pb target and take the weighted mean and its error for rskin208(PREX2), three skin values of p+208Pb, 3,4He+208Pb scattering and rskin208=0.102∼0.354fm based on the 206 EoSs. As the second aim, we determine matter radii rm(exp) of 58,60,64Ni from σR(exp) of 3,4He scattering on 58,60,64Ni targets. Results:Our result is rskin208(exp)=0.512±0.268fm for 3He+208Pb scattering. Our results based on 4He+58,60,64Ni scattering are rm58(exp)=3.734±0.091 fm, rm60(exp)=3.815±0.094 fm, rm64(exp)=4.001±0.093 fm. Our results based on 3He+58,60,64Ni scattering are rm58(exp)=3.709±0.098 fm, rm60(exp)=3.753±0.112 fm, rm64(exp)=3.822±0.142 fm. Conclusion:Our conclusion is rskin208=0.285±0.030fm. It is determined from the 5 skin values mentioned above.