Low-Lying Level Structure of theZn65Nucleus

Sulfur and beryllium samples have been used as energy-selective neutron absorbers to investigate the low-lying level structure of the ${\mathrm{Zn}}^{65}$ nucleus. The transmission through the samples of the neutrons from the ${\mathrm{Cu}}^{65}(p, n){\mathrm{Zn}}^{65}$ reaction was measured as a function of the proton energy and the known resonances in the neutron total cross sections of S and Be were observed for both the neutron group leaving ${\mathrm{Zn}}^{65}$ in the ground state and for a group leaving ${\mathrm{Zn}}^{65}$ in an excited state at 118±8 kev. At a proton energy of 2.9 Mev, these two groups are of approximately the same intensity. The $Q$-value for the ${\mathrm{Cu}}^{65}(p, n){\mathrm{Zn}}^{65}$ reaction was found to be -2.141±0.005 Mev. The 585-kev resonance in S was observed with neutrons from the ${\mathrm{V}}^{51}(p, n){\mathrm{Cr}}^{51}$ reaction and the threshold energy of 1.566 Mev for this reaction was confirmed.