ELECTRON-EMISSION FROM ALIGNED SUPEREXCITED O-ASTERISK ATOMS PRODUCEDIN PHOTODISSOCIATION OF O-2 IN THE 22.20-22.36 EV REGION

Photoelectron photoion coincidence and threshold photoelectron photoio n coincidence time of flight spectra for O-2 molecules in the 22.20-22 .36 eV region have been measured to investigate anisotropy in dissocia tive photoionization processes. Some of the Of ions were produced in a particular photodissociation process in which the molecule fragments into an O(P-3) atom and an excited O[P-2(o) 3d('')] atom, which autoi onizes to produce O+(D-2(o)) + e(-)(0.16 eV). The O+ spectra present a nonisotropic profile which is interpreted as the result of a photodis sociation process producing aligned O atoms followed by ejection of a n electron along the axis of the dissociating molecule.