The deviations of the ${\pi }^{\pm }$-induced neutron knockout cross section ratios from the impulse approximation, as measured in a recent deexcitation $\gamma$ ray experiment on ${}_{}{}^7{}_{}{}^{}\mathrm{Li}$, are shown to be in good agreement with the modified nucleon charge exchange model with reasonable charge exchange probabilities.

NUCLEAR REACTIONS Ratios of $\sigma \left[{}_{}{}^7{}_{}{}^{}\mathrm{Li}\right({\pi }^{\pm }, \pi N\left){}_{}{}^6{}_{}{}^{}\mathrm{Li}_{}^{*}{}_{}{}^{}\right(3.56\mathrm{} \mathrm{MeV}]$, detect deexcitation $\gamma$, $T_{\pi }=50\mathrm{} \mathrm{to} 290$ MeV, probability of recoil nucleon charge exchange.

• Received 22 November 1976

DOI:https://doi.org/10.1103/PhysRevC.15.1158