FLUORESCENCE EXCITATION-FUNCTION OF NI 1200-ANGSTROM A AND CROSS-SECTIONS FOR FLUORESCENCE PHOTON-PHOTOION COINCIDENCE PRODUCED THROUGH PHOTOEXCITATION OF N2

The absolute fluorescence excitation function of the NI 1200-angstrom emission through photoexcitation of N2 has been measured in the 250-62 0 angstrom region using synchrotron radiation as the continuous tunabl e light source. The dissociative photoionization excitation of N2 invo lving the production of NI 1200-angstrom emission and N+ ion has also been studied at several selected photon wavelengths shortward of 360 a ngstrom using a coincidence technique to detect the NI 1200-angstrom f luorescence photon and the N+ ion. The maximum quantum yields for prod ucing these processes are of the order of 6 x 10(-2). It was found tha t dissociative excitation processes can be competitive with the dissoc iative ionization excitation processes for the multiple-electron trans ition states. The present results suggest that the electronic states o f N2 in the 320-340 angstrom region consist of both ion states of N2(Langhoff et al., 1981) and neutral states of N2, which could be the R ydberg states converging to N2++ (Sambe and Ramaker, 1986).