Generalized oscillator strength for the argon 3p6-3p54s transition:: Correlation and exchange effects on the characteristic minimum

We have investigated the generalized oscillator strength (GOS) for a transition of the type np->(n + 1)s, where n is the principal quantum number of the outermost filled shell of the atomic ground state, using the random-phase approximation with exchange. We find that the influence of correlation and exchange effects on the position of the characteristic minimum in the GOS of Ar(n =3) is insignificant. Also, our first Born approximation predicts the position of the minimum accurately provided that accurate target wave functions are employed. Our results agree excellently with measurements and are expected to be applicable equally to the corresponding subshells of Ne(n = 2), Kr(n = 4), and Xe(n = 5).