Generalized oscillator strength for the potassium resonance transition

The generalized oscillator strength (GOS) is an important property of the atom which manifests the atomic wavefunction directly. GOSs for the potassium resonance transition have been investigated using the spin-polarized technique of the random-phase approximation with exchange (RPAE) and the Hartree-Fock approximation (HFA). Two minima are predicted by both calculations. The first minimum, which is narrower and has never been measured before, is predicted by the RPAE at a momentum transfer value of K = 0.8838 au, while the second is the well measured one at 2.907 au. The positions of the minima are found to be influenced by inter-shell correlations significantly. We recommend a careful experimental search for the first minimum around the predicted value.