Experimental determination of the effective contributions of the L+M and K electrons of argon to the Bethe sum rule

Energy loss spectra over a large energy loss range have been obtained for Ar using high energy electron impact spectroscopy. The sums of the generalized oscillator strengths for all possible excitation and ionization transitions have been determined separately for the L+M and K shell electrons relative to the Bethe sum rule for the whole atom. The effective number of electrons NK in the K shell of Ar was determined and found to be the same as theoretical predictions and experimental determinations for dipole oscillator strengths. (AIP)