Electron coincidence spectroscopy of sodium and potassium

Abstract

The Na 3s and K 4s electron momentum distributions have been obtained using the non-coplanar symmetric (e,2e) reaction at total energies of 800 and 1200 eV. They show excellent agreement with the results of plane-wave impulse approximation calculations using Roothaan-Hartree-Fock functions, after small corrections are made for the finite angular resolution of the apparatus. The potassium valence s momentum profile is a little narrower than that for sodium, implying a correspondingly slightly larger spatial distribution of the outer valence electrons. The ratios between the (n-1)p and ns cross sections at their respective maxima in q space were measured to be 0.009+or-0.0093 and 0.019+or-0.003 for Na and K respectively. These cross section ratios are in agreement with the PWIA calculations. Show more