The Widths of Nuclear Energy Levels

Neutron absorption measurements with Rh both as absorber and detector have been performed, in order to obtain information about the levels of the compound nucleus responsible for the 44{''} period of Rh. The absorption curves have been analyzed by assuming a single sharp resonance and taking into consideration the angular distribution of the neutrons emerging from the source and the absorption of the neutrons and the electrons in the detector. This analysis yields the values: (a) 6100×{}10^-24 cm² for the capture cross section at resonance; (b) 0.17 ev for the total width; (c) 1.6×{}10^-3 ev for the neutron width.