DIRECT DETERMINATION OF PARTIAL-WAVE CONTRIBUTIONS IN THE SIGMA-ASTERISK SHAPE RESONANCE OF CO MOLECULES

The first complete experiment for the C K-shell of CO molecules in the region of the sigma shape resonance has been performed by detecting photoelectrons in coincidence with fragment ions. Four ratios of dipol e matrix elements and four phase shift differences have been extracted from the experi mental data. Their analyses show that, in the sigma shape resonance due to the l mixing, d and f partial waves give the ma in contribution to the cross section, and f and g waves give the main contribution to a rapid increase of phase shift by pi.