Production Mechanisms and Radiative Lifetimes of Argon and Xenon Molecules Emitting in the Ultraviolet

Abstract

The time dependences of uv emissions from dense argon and xenon are monitored following low-intensity electron excitation. The uv transitions originate on the lowest ${0}_{\mathrm{u}}^{+}$ and ${1}_{\mathrm{u}}$ molecular states. For argon the radiative lifetimes are 3.2\ifmmode\pm\else\textpm\fi{}0.3 \ensuremath{\mu}sec (${1}_{\mathrm{u}}$) and 4.20\ifmmode\pm\else\textpm\fi{}0.13 nsec (${0}_{\mathrm{u}}^{+}$), while for xenon they are 96\ifmmode\pm\else\textpm\fi{}5 and 5.5\ifmmode\pm\else\textpm\fi{}1.0 nsec. The radiating molecules are formed by three-body destruction of excited atoms; the rate coefficient for argon is (2.8\ifmmode\pm\else\textpm\fi{}0.3) \ifmmode\times\else\texttimes\fi{} ${10}^{\ensuremath{-}33}$ ${\mathrm{cm}}^{6}$/sec.