EXCITATION OF THE 3P'[1 2](0) STATE OF NEON BY HIGH-RESOLUTION ELECTRON-IMPACT/

We have measured the electron-impact excitation function for the 3p'[1 /2] J = 0 excited state of neon at energies from threshold (18.966 eV) to about 20.6 eV. The measurements have been carried out with a high- resolution (20 meV) electron spectrometer by detecting the yield of 58 52 Angstrom radiation, emitted in the decay of the 3p' state to the 3s '[1/2] J = 1 level (the 2p(1) --> Is(2) transition in Paschen notation ), as a function of the incident energy. The excitation function has a lso been calculated using a modified version of the Breit-Pauli R-matr ix codes of Berrington et al in a 31-state calculation. The agreement between experiment and theory is encouraging, particularly with regard to the presence of a number of negative-ion resonances. Conclusions r egarding the previous classifications of these resonances are drawn.