ALPHA RADIATION OF U$sup 23$$sup 3$

A magnetic alpha spectrometer was used for investigating the U/sup 233/ spectrum from two sources. The half-width of the spectral line of the first source was 8 kev and of the second 10 kev. Measurements showed in addition to the known transi tion lines, daughter lines of Th/sup 229/ with energies of 29, 72, 126, and 195 kev, which fit well into the rotational band with quantum number k= 5/2 initiaied at 29 kev. The experimental ratio of the band energies is 1:2.26: 3.87 and the theoretical is 1: 2.28: 3.86. An analysis of the excited level of Th/sup 229/ indicates a quantum number of 5/2-- for the 29 kev level and for the 72, 126, and 195 kev levels, 7/2--, 9/2--, and 11/2--, respectively. The decay scheme for U/sup 233/ is presented. (R.V.J.)