Deactivation of krypton atoms in the metastable 5s(³P₂) state in collisions with krypton and argon atoms

Quenching of Metastable 5 s′(3P0) Krypton Atoms in Collisions with Krypton and Argon Atoms in High-Pressure Laser Mixtures

“…The results obtained in the present work (see also [1,2]) showed that, under the mentioned experimental conditions, the collisional quenching of the metastable 5s ( 3 P 0 ) krypton atoms in Ar-Kr mixtures occurs through the tree-body reaction (1) with formation of a Kr * 2 homonuclear dimer and two-body reaction (3). The three-body reaction (2) with the formation of ArKr * heteronuclear dimer has a negligibly small rate constant and, therefore, can be ignored.…”

“…This fact results in extra absorption and slight concavity at the beginning part of the curve in Fig. 4 b. Consequently, the collision-induced decay of the Kr(5s) levels is so slow that one must take into account even the influence of low recombination flues, which continue to populate the level in question in the afterglow at the end of e-beam pulse (see [1,2]). This seems to be a reason for a certain convexity of the ln ln(1/T ) dependence in Fig.…”

“…The first fast decaying term on the right-hand side of (13), i.e., p ex exp − k ex (t − t 0 ) , describes a broadband absorption (with γ = 1) of the probe pulse by the excimer molecules, whereas in the second slowly decaying term p d exp − (γg(t − t 0 )) 2 exp − γk d (t − t 0 ) , the term exp − γk d (t − t 0 ) describes the decay rate of interest, and the Gaussian-type term exp − (γg(t − t 0 )) 2 provides a correction for recombination and relaxation processes populating the 5 s ( 3 P 0 ) state [1,2]. Obtaining the true form of the Gaussian-type factor in an analytical form is hardly possible because of the variety and complexity of related reactions depending, in particular, on the time-varying temperature and density of the secondary electrons.…”

“…In this paper, we continue our study on the plasma-chemical reactions for collisional quenching excited 5s states of krypton atoms in high-pressure Ar-Kr mixtures [1,2]. These experiments are a part of our long-term research on quenching the lower atomic s-states of neon, krypton, and xenon rare gases in high-pressure (p > 1 atm) binary mixtures with a large amount of lighter rare gas, acting as a buffer gas (see reviews [3,4] and references therein and more recent publications [5][6][7]).…”

“…The rate constants here are obtained by the absorption probe technique [1][2][3][4][5][6][7], by monitoring the decay time of the state under study as a function of pressure and component ratio of the working and buffer gases. Finally, time-resolved absorption is measured in the afterglow of a high-power e-beam pulse using a probing light pulse at wavelength λ = 0.7855 μm, corresponding to a high-oscillator-strength optical The experiments were carried out with the coldcathode electron gun of the Tandem pulsed laser system described in [12].…”