Electron impact excitation of the 3d104p 2P state in copper

Differential and total cross sections for the excitation of the 3d104p state in copper by electrons have been measured at incident energies of 20, 40, 60, 80 and 100 eV. The differential cross sections cover the angular range from 2.5o to 130o. Absolute values of the cross sections have been assigned using a generalized oscillator strength technique and the validity of this technique is explored in some detail. The measured cross sections are compared with those predicted by several theories where it is found that the close-coupling calculation of Msezane and Henry accurately predicts the value of the total cross sections for incident energies greater than 20 eV. Agreement between theory and experiment for the differential cross sections is poor. The present measurements of the differential cross sections resolves the ambiguity in the absolute values of the cross sections measured by Trajmar and coworkers. (author)