Excitation of 107m,109mAg isomeric states in the inelastic scattering of fast neutrons from the IBR-2 reactor of JINR

The cross sections for the excitation of long-lived isomers of 107,109Ag nuclei are measured in the inelastic scattering of fast neutrons from the IBR-2 reactor of JINR (Dubna). The measurements are performed by means of comparison with the yield of the 103mRh isomer, for which the excitation cross sections are known over a wide energy range for similar reactions induced by monochromatic neutrons. The measured cross sections proved to be σ(107mAg)=204±18 mb and σ(109mAg)=262±26 mb. These values are significantly smaller than the cross section for the excitation of the 103mRh isomer. An analysis employing information about the arrangement of energy levels in Rh and Ag and about transitions between these levels, as well as data on the spectra of γ rays emitted in (n,n'γ) reactions, reveals that the distinction between the cross sections for the excitation of Rh and Ag isomers can be explained by the difference in the population of corresponding levels of Rh and Ag nuclei