Study of charge symmetry inHe4by simultaneousHe4(e,e’p)3H andHe4(e,e’n)3He measurements

We have measured the ${(}^3$H+p) and ${(}^3$He+n) breakup of ${}_{}{}^4{}_{}{}^{}\mathrm{He}$ by ${}_{}{}^4{}_{}{}^{}\mathrm{He}$(e,e’c) coincidence experiments at low momentum transfer (q≊0.39 ${\mathrm{fm}}^{\mathrm{-}1}$) in the excitation energy region 22≤$E_x$≤36 MeV. Both channels were studied simultaneously by detecting the charged fragments c=p, ${}_{}{}^3{}_{}{}^{}\mathrm{H}$, and ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ in the same detector system. The measured ${}_{}{}^4{}_{}{}^{}\mathrm{He}$(e,e’p${)}^3$H and ${}_{}{}^4{}_{}{}^{}\mathrm{He}$(e,e’n${)}^3$He angular correlations as well as the deduced total ${}_{}{}^4{}_{}{}^{}\mathrm{He}$(e,e’p${)}^3$H and ${}_{}{}^4{}_{}{}^{}\mathrm{He}$(e,e’n${)}^3$He cross sections are reproduced by microscopic model calculations with a charge-symmetric nuclear Hamiltonian.