Collisional and radiative excitation transfers in Kr-Xe mixtures: Emissions from the Xe(3P1) resonant level and the Xe first continuum region.

Abstract

Time-dependent and time-independent measurements of emissions from Xe in Kr-Xe mixtures are reported. Kr host gas pressure was varied from 100 to 900 Torr, and Xe impurities were varied from 1% to 10% of total Kr pressure. This work has shown that the Xe${(}^{3}$${\mathit{P}}_{1}$) resonant state is depopulated by collisions with both Xe and Kr ground-state atoms. In particular, a two-body quenching rate of 10 $^{4}\mathrm{P}_{\mathrm{Xe}}$+2100${\mathit{P}}_{\mathrm{Kr}}$ is reported. This two-body rate is assigned to represent a collisional transition to the Xe${(}^{3}$${\mathit{P}}_{2}$) metastable state. A three-body rate of 97${\mathit{P}}_{\mathrm{Xe}}$${\mathit{P}}_{\mathrm{Kr}}$+7${\mathit{P}}_{\mathrm{Kr}}^{2}$ was also found. The rate 7${\mathit{P}}_{\mathrm{Kr}}^{2}$ is assigned to represent the formation of (KrXe${)}^{\mathrm{*}}$ molecules, while the rate 97${\mathit{P}}_{\mathrm{Xe}}$${\mathit{P}}_{\mathrm{Kr}}$ represents either formation of ${\mathrm{Xe}}_{2}^{\mathrm{*}}$(${\mathrm{O}}_{\mathit{u}}^{+}$) or (XeKr${)}^{\mathrm{*}}$. Time-dependent measurements made in the Xe first continuum region at about 1500 \AA{} indicate that these emissions follow the Xe${(}^{3}$${\mathit{P}}_{1}$) state.