Gamma Radiation from Certain Nuclear Reactions

Abstract

The gamma radiation from five nuclear reactions has been studied with a single NaI crystal. Three new resonances in the emission of 12-Mev radiation from the reaction ${\mathrm{F}}^{19}(p, \ensuremath{\gamma}){\mathrm{Ne}}^{20}$ have been found at 1092-kev, 1324-kev, and 1431-kev bombarding energy. The widths are, respectively, 1.2 kev, 4.0 kev, and 15.7 kev, and the cross sections at resonance are >0.05 mb, 0.081 mb, and 0.19 mb, respectively. The first resonance corresponds to one in the reaction ${\mathrm{F}}^{19}(p, \ensuremath{\alpha}\ensuremath{\gamma}){\mathrm{O}}^{16}$, whereas the last two do not. All the transitions are to the 1.63-Mev level in ${\mathrm{Ne}}^{20}$ or to a nearby level. Possible values of the spin and parity of the excited levels in ${\mathrm{Ne}}^{20}$ are discussed.A search was made for gamma radiation from the bombardment of lithium by 650-kev deuterons. Upper limits for the production of 5-, 6-, and 7-Mev gamma rays are 2 mb, 1 mb, and 0.5 mb, respectively.A search was made for the radiative capture of deuterons in the bombardment of deuterium, helium, and oxygen. No capture gamma rays were observed, and upper limits for the cross section for these reactions are: ${\mathrm{D}}_{2}$, 0.05 \ensuremath{\mu}b at a deuteron energy of 1260 kev; He, 0.1 mb at 1055 kev; and ${\mathrm{O}}_{2}$, 0.5 mb at 1100 kev.