Matter radii and skins of ^6,8He from reaction cross section of proton+^6,8He scattering based on the Love–Franey t-matrix model

Background: For ^4,6,8He, Tanihata et al. determined matter radii r_m(σ_I)=1.57(4),2.48(3),2.52(3) fm from interaction cross sections σ_I for ^4,6,8He scattering on Be, C Al targets at 790 MeV/nucleon. Lu et al. measured the atomic isotope shifts (AIS) for ^4,6,8He and determined proton radii r_p(AIS) for ^4,6,8He. As for p+^4,6,8He scattering, reaction cross sections σ_R(exp) are available at 700 MeV with high accuracy. Aim: Our aim is to determine matter radii r_m and skins r_skin for ^6,8He from the σ_R(exp) and the r_p(AIS). Method: Our model is the Love–Franey t-matrix folding model, since the model is better than the optical limit of Glauber model. Results: Our results for ^6,8He are r_m(exp)=2.48(3),2.53(2) fm and r_skin=0.78(3), 0.82(2) fm. Conclusion: For ^6,8He, our results r_m(σ_R) agree with those of Tanihata et al. For ⁸He, the distance between ⁴He and the center of mass of valence four neutrons is 2.367 fm.