MEASUREMENTS OF THE K-SHELL IONIZATION CROSS-SECTIONS IN MN-25, FE-26, CO-27 AND NI-28 BY 260-400-KEV PROTONS

K-shell X-ray production cross-sections (sigma(kappaalpha)chi and sigm a(kbeta)X) have been measured for thick targets of 25Mn, 26Fe, 27Co an d 28Ni at incident proton energies in the range 260-400 keV at an inte rval of 20 keV. The K-shell ionization cross-sections inferred from th ese results at various energies, have been compared with the empirical reference cross-sections and the theoretical values based on the ECPS SR theory by plotting the sigma(exp)I/sigma(ECPSSR)I and sigma(exp)I/s igma(Ref)I against the proton energy and the reduced ion velocity. The present results are found to be in reasonable agreement with the empi rical reference cross-sections of Paul and Sacher6 and the result base d on the ECPSSR theory.