Neutron skin thickness of ^{116,118,120,122,124}Sn determined from reaction cross sections of proton scattering

Background: The cross sections of the isovector spin-dipole resonances (SDR) in the Sb isotopes have been measured. Within the model used, the neutron-skin thicknesses r_skin(exp) deduced 0.12±0.06 fm for ¹¹⁶Sn, 0.13±0.06 fm for ¹¹⁸Sn, 0.18±0.07 fm for ¹²⁰Sn, 0.22±0.07 fm for ¹²²Sn, 0.19±0.07 fm for ¹²⁴Sn. We tested the chiral (Kyushu) g-matrix folding model for ¹²C+¹²C scattering, and found that the Kyushu g-matrix folding model is reliable for reaction cross sections σ_R in 30˜<E_in˜<100MeV and 250˜<E_in˜<400MeV. We determine neutron skin thickness r_skin(exp), using measured σ_R of ⁴He+^116,120,224Sn scattering. The results are r_skin(exp)=0.242±0.140 fm for ¹¹⁶Sn, r_skin(exp)=0.377±0.140 fm for ¹²⁰Sn, r_skin(exp)=0.180±0.142 fm for ¹²⁴Sn. The σ_R are available for proton scattering on ^{116,118,120,122,124}Sn with high accuracy of 2∼3% as a function of incident energy E_in. Purpose: Our aim is to determine r_skin(exp) for ^{116,118,120,122,124}Sn with small errors by using the Kyushu g-matrix folding model. Methods: Our model is the Kyushu g-matrix folding model with the densities scaled from the D1S-GHFB+AMP neutron density, where D1S-GHFB+AMP stands for Gogny-D1S HFB (D1S-GHFB) with the angular momentum projection (AMP). Results: The proton radii of D1S-GHFB+AMP agree with those calculated with the isotope shift method based on the electron scattering. We then scale the D1S-GHFB+AMP neutron densities so as to reproduce the σ_R(exp). In 30˜<E_in˜<65MeV, we determine r_skin(exp) from measured σ_R. The values are r_skin(exp)=0.118±0.021 fm for ¹¹⁶Sn, 0.112±0.021 fm for ¹¹⁸Sn, 0.124±0.021 fm for ¹²⁰Sn, 0.156±0.022 fm for ¹²⁴Sn. As for ¹²²Sn, the skin value in 30˜<E_in˜<50MeV is 0.122±0.024 fm. Conclusions: Our results are consistent with the previous values.