抄録
Spectra of deuterons from (p, d) reactions on 18 nuclei with neutron numbers N between 52 and 82 were measured at an angle of 20° with 52-MeV incident protons. In each spectrum a broad bump with the distinct top is observed at excitation energies of several MeV or higher. From the systematic behavior of the bump it is inferred that the top of the bump stands for an approximate position of the 1 g9⁄2 neutron state, and energies of this state are estimated from the observed spectra. The estimated energies are compared with calculated ones and a reasonable agreement is obtained. The systematics of the energy difference between the top of the bump and the ground state in the residual nucleus is discussed on the basis of the simple pairing theory, and the results which are well consistent with the above inference about the top of the bump are obtained.
