Electron impact excitation of the lowest-lying excited states of krypton

Excitation of the 4p 5 ( 2 P 3 2/)5s 3 P 1 and 4p 5 ( 2 P 1 2/)5s 1 P 1 states of krypton by electron impact has been studied using the electron-photon angular correlation technique. Measurements are reported at an incident electron energy of 60 eV for electron scattering angles theta e up to 30 degrees . The serious disagreement between two previous measurements at theta e =20 degrees is discussed. The difficulty of obtaining a quantitative measure of the importance of spin-orbit coupling through the parameter epsilon using this technique is demonstrated.