Systematics of the (p, n) excitation functions belonged to several isotopes at energies <60 MeV

Excitation functions of proton induced charge exchange reaction on nuclei between A = 11 and 238 are studied. All the studied excitation functions of (p, n) reaction show systematic variation with atomic mass in connection with nucleon binding energy. Islands of higher reaction yield appeared to be for nuclei with mass number A = 49, 72, 89, 109, and 139, and proton energy range from 9 to 12 MeV. The more probable occurrence of proton induced charge exchange reaction in these regions are attributed to its extra binding energy per nucleon than other nuclei. The larger contribution of pre-equilibrium processes on the neutron emission appeared on the linearity of the log(σ)-log(Ep) in some energy ranges. The slopes of these linear segments may be related to the excitons configuration in which the neutron is emitted by.