Fluorescence decay of the O_u⁺ and 1_u states of Xe₂

Synchrotron radiation from the Stanford storage ring (SPEAR) was used to measure the radiative decay constants of the lowest-lying excited electronic states of Xe₂. Both a monochromator and interference filters were used in the fluorescence channel. The results suggest that at low pressures (P_Xe<125 Torr) there is substantial deviation from the Stern-Volmer behavior predicted by the three-state models used previously to describe this lasing system. A new theoretical analysis was developed that includes participation in the kinetic scheme of intermediate vibrational levels of the O_u⁺ and 1_u manifolds.