Oscillator strengths and electron-excitation cross sections for atomic nitrogen

The LS states belonging to the configurations 2s(2)2p(3), 2s2p(4), 2s(2)2p( 2)3s. 2s(2)2p(2)3p, 2s(2)2p(2)3d, and 2s(2)2p(2)4s of neutral nitrogen are considered in the calculations of excitation energies and oscillator streng ths. Extensive configuration interaction wave functions are used, which giv e excitation energies in close agreement with the experiment. The calculati on of the differential and integral cross sections of the forbidden S-4(o)- D-2(o) transition for the scattering of electrons from atomic nitrogen is p erformed in a Ii-state close-coupling approximation using the R-matrix meth od in the energy region from threshold to 70 eV. The calculated differentia l cross sections are peaked in the backward direction and compare very well with the recent measurement. The present integral cross sections also show very good agreement with the available other calculations and measurement. [S1050-2947(99)10205-1].