Electron impact excitation of potassium at 6.7, 16 and 60 eV

Normalized momentum-transfer cross sections and differential and integral cross sections for elastic scattering and for the excitation of the 4p 2 P 3/2,1/2 and the (5s 2 S 1/2 + 3d 2 D 5/2,3/2 ) levels in potassium are reported. There is considerable disagreement between the present experimental results and previous optical excitation measurements and theoretical results. Autoionization features associated with the 3p inner-shell excitations, some of which have been observed previously in optical absorption and ejected-electron spectra, have been detected in the electron impact energy-loss spectrum.