Quenching of the resonance 5s(³P₁) state of krypton atoms in collisions with krypton and helium atoms

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

“…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].…”

On the possibility of developing quasi-CW high-power high-pressure laser on 4p–4s transition of ArI with electron beam—optical pumping: quenching of 4s (3P2) lower laser level

“…A new approach to the development of high-power high-pressure quasi-cw He-Ar laser with a large volume of gain medium at Ar dimer with rate constant 3.610 -33 cm 6 /s and quenching by buffer gas with rate constant 2.410 -15 cm 3 /s, whereas the reaction with formation of the heteronuclear dimer plays virtually no role. The measurements demonstrated that the rate of collisional quenching of o 2 4s[3/2] state is low being considerably inferior to the rates of similar processes in the mixtures of other rare gases measured earlier in [10][11][12][13][14][15][16]. This circumstance does indicate that production and maintenance of the necessary amount of argon atoms in o 2 4s[3/2] state is feasible at very moderate current densities of pumping electron beam readily attainable with, e.g., hot-cathode electron guns whose pulse width can be easily regulated up to a cw mode of operation.…”

“…Thus, the measured effective rate constant for the formation of HeAr* dimer happens to be negligible. being considerably inferior to the rates of similar processes in the mixtures of other rare gases measured earlier in [10][11][12][13][14][15][16]. This circumstance does indicate that production and maintenance of the necessary amount of argon atoms in o 2 4s[3/2] state is feasible at very moderate current densities of pumping electron beam readily attainable with, e.g., hot-cathode electron guns whose pulse width can be easily regulated up to a cw mode of operation.…”

“…A set of experimental data for the mixtures He-Ar = 50:1, 75:1, 100:1 and 200:1 at gas pressures from p = 1.75 to 4.0 atm was numerically calculated with a step of 0.25 atm. In the coordinates of figure 5a the function (12) corresponds to the function ln(1/T) = p ex exp(-k ex (t-t 0 )) + p d exp(-(γg (t-t 0 )) 2 ) exp(-γk d (t-t 0 )), (13) where the first, slowly-decaying term of the right-hand side of (13) p ex exp(-k ex (t-t 0 )) (14) describes a broadband absorption (γ = 1) of the probe pulse by the excimer molecules, whereas the second term p d exp(-(γg (t-t 0 )) 2 ) exp(-γk d (t-t 0 )) (15) describes the studied exponential process of collisional quenching of o 2 4s[3/2] metastable state exp(-γk d (t-t 0 )) (16) with "Gaussian pre-exponent" exp(-(γg (t-t 0 )) 2 ), (17) which provides a correction for the recombination and relaxation processes of populating this state [11,12]. Obtaining a true form of the Gaussian pre-exponent in analytical form is hardly possible because of the variety and complexity of the relevant reactions depending, in particular, on the time-varying temperature and density of the secondary electrons.…”