Radiative Proton Capture byNi58,Ni60, andCo59

Abstract

Thin targets of ${\mathrm{Ni}}^{58}$, ${\mathrm{Ni}}^{60}$, and ${\mathrm{Co}}^{59}$ were bombarded with protons from 700 to 1900 kev. Seventeen radiative capture resonances were observed for ${\mathrm{Ni}}^{58}$; fifty-four resonances were observed for ${\mathrm{Ni}}^{60}$; and about 150 resonances were observed for ${\mathrm{Co}}^{59}$. Precise bombarding energies were determined for the nickel resonances, and are listed in tabular form. All resonances were narrower than 1 kev. The $\int \sigma \mathrm{}\left(E\right)\mathrm{dE}$ was measured for each of the nickel resonances. The following $Q$ values were determined: ${\mathrm{Ni}}^{58}(p, \gamma ){\mathrm{Cu}}^{59}$, 3.42±0.02 Mev; ${\mathrm{Ni}}^{60}(p, \gamma ){\mathrm{Cu}}^{61}$, 4.81±0.03 Mev. The following low-energy cascade gamma rays were observed: ${\mathrm{Ni}}^{58}$, 0.492±0.005, 0.908±0.020, 1.38±0.03, 1.78±0.02, 2.00±0.04, and 2.32±0.04 Mev; ${\mathrm{Ni}}^{60}$, 0.468±0.010, 0.96±0.02, 1.30±0.02, 1.38±0.02, 1.63±0.03, and 1.91±0.03 Mev; ${\mathrm{Co}}^{59}$, 0.47±0.02, 0.84±0.02, 0.95±0.02, 1.07±0.02, 1.17±0.02, 1.33±0.02, 1.64±0.03, and 1.77±0.03 Mev. Branching ratios to all states below 2 Mev were measured from several of the intense resonances in the nickel isotopes. The branching ratio measurements indicated that the low-energy member of each cascade in the nickel reactions, except possibly the 1.30-Mev gamma ray from protons on ${\mathrm{Ni}}^{60}$, represented an excited state of the same energy; but indications for a 1.38-Mev state in ${\mathrm{Cu}}^{59}$ and a 1.63-Mev state in ${\mathrm{Cu}}^{61}$ were weak. Angular distribution measurements were made on some of the more intense resonances in the nickel isotopes, and unique spins were determined for those resonant states and for the first excited state of ${\mathrm{Cu}}^{59}$. For the states whose spins were measured, probable parity assignments have been made. Reduced proton widths have been determined for the resonances below a bombarding energy of 1300 kev. The matrix elements for the several $E1\mathrm{}$ and $M1\mathrm{}$ transitions are compared with previous tabulations. Several new experimental techniques are discussed.