Energy and Intensity of the Gamma Radiation from F¹⁹ and H¹ and Be⁹ and D²

A magnetic lens β-ray spectrometer with a large (~4.5% of a sphere) solid angle and with good shielding against the neutron and ý-ray backgrounds encountered in the investigation of the prompt ý-radiation from nuclear reactions is described. Methods for determining the intensities of ý-radiation by observation of photoelectron and C01npton electron secondaries with the spectrometer are discussed. It is concluded that when their use is feasible, Compton secondaries will give the more accurate values for the intensity and energy or ý-radiation. The nuclear pairs and y-radiation from excited states of O16 have been investigated. The pair spectrum agrees well with that calculated theoretically, and the end point indicates that the first excited state of O16 is at 6.04 ± 0.03 Mev. The ý-radiation observed corresponds to levels et 7.09 ± 0.06, 6.9, and 6.14 ± 0.04 Mev. Estimates of the relative and absolute intensities of the ý-radiation are given. The rather complicated y-ray spectrum resulting from the bombardment of beryllium with deuterons has been investigated. The assignment of these ý-rays to the possible residual nuclei is discussed, and it is determined that most of them can be attributed to excited states of B10, as formed 1n the Be9 (d,n) B10 reaction. By comparing the ý-ray intensities with the neutron intensities observed by other experimenters, a level scheme for B10is constructed.