A large liquid scintillator with approximately 80 percent efficiency for detection of neutrons has been used to obtain data on numbers of neutrons emitted per fission for several fissioning nuclides. Reported here are the average number of neutrons per fission, v, and the respective probabilities of 0,1, 2, • • • neutrons per fission, for spontaneous fission of_Pu 240 , Cm 244 , and Cf 252 , and for fission induced in U 233 , U 235 , and Pu 239 by 80-kev neutrons. The values of v for these cases are, respectively, 2.257±0.045, 2.810±0.059, 3.869 ±0.078, 2.585±0.062, 2.47±0.03, and 3.048±0.079. The thermal neutron value for U 235 (2.46=1=0.03), obtained by other methods, was used here as a standard for calibrating the detector efficiency. The efficiency was also measured by another method, involving scattering neutrons into the scintillator, with results in good agreement. The probabilities of 0, 1, 2,---neutrons per fission approach closely a binomial type distribution, with the maximum number of neutrons equal to 5, 6, or 7, depending on p.

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Yield and angular distribution measurements on the T 3 (/>, 7)He 4 reaction have been made for protons up to 2.5 Mev. The yield indicates a resonance in the He 4 nucleus at a proton energy of about 2.5 Mev, giving an excited level at 21.6 Mev. The angular yield of the gamma-rays fits an A-\-B sin 2 # distribution very well, suggesting that the gamma-rays are due predominantly to a transition from the x Pi state to the 1 SQ state. An aluminum absorption curve for the secondaries produced in a lead radiator was taken, and a direct comparison made with the 17.5-Mev gamma-rays from the Li 7 (p, 7)Be 8 reaction, showing that the T 3 (/>, 7)He 4 gamma-rays are of higher energy.