A study of K x-ray nuclear satellites from (p, chi n) reactions on heavy elements

This paper reports the K-shell ionisation cross sections for the reaction products from the 7-15 MeV proton bombardment of the following targets (with atomic number Z): 160Gd, 171172173174Yb, 181Ta, 192Os, 197Au, 208Pb and 232Th. The results are interpreted within the assumption that the vacancy production in the K shell of the Z + 1 atom is due to the internal conversion of the gamma transitions de-exciting the (p, chin) reaction products. The average number of K-shell vacancies per reaction event varies from 0.6 for rare earths to 0.08 in the lead region, in close correlation with the density of the low-lying levels in the final nuclei. The sensitivity of the satellite x-ray cross section to the low-energy M1 transitions in heavy nuclei is pointed out. (author)