Effective production of Xe2I excimer molecules by high-energy charged particles in Xe containing a small amount of C3F7I

An anomalously high efficiency of generating Xe2I* excimer molecules in dense Xe–C3F7I gaseous mixtures with a small amount of C3F7I that are excited by a pulsed beam of fast electrons is discovered. The electron energy is 150 keV, and the beam current amplitude and duration are, respectively, 5 A and 5 ns. The temporal–spectral characteristics of spontaneous radiation from XeI* and Xe2I* excimer molecules are measured. Also, the luminescence times of the upper level for the B–X transition in the XeI* molecule (λmax = 253 nm) and the upper level for the 42Γ–12Γ transition in the Xe2I* molecule (λ = 352 nm), as well as the rate constants of quenching these levels by the gaseous mixture components, are determined. Based on the characteristics of the track structure of a high-energy plasma produced by charged particles in the dense gaseous medium, a model of plasma-chemical processes leading to the formation of XeI* (λmax = 253 nm) and Xe2I* (λ = 352 nmnm) excimer molecules in a Xe–C3F7I mixture with a small amount of an iodine atom donor is suggested.