ELECTRON-IMPACT EXCITATION OF NEUTRAL ATOMIC OXYGEN (P-3-]D-1, P-3-]S-1 AND D-1-]S-1 TRANSITIONS)

The R-matrix method is employed to calculate the total cross section f or electron-impact excitation of the P-3 --> D-1, P-3 --> S-1 and D-1 --> S-1 transitions in neutral oxygen. Nineteen spectroscopic states t ogether with 12 pseudo-states are included in the R-matrix wavefunctio n expansion. The pseudo-states are chosen to ensure that the static di pole polarizability is fully included for all of the three transition states. Although the present calculation is the largest ever performed for neutral oxygen, discrepancies are found for all three transitions between the present theoretical results and experimental data. It is essential that further experiments be performed.