<title>Luminescence of nuclear-induced rare-gas plasmas in near infrared spectral range</title>

Mechanisms of level population in gas lasers pumped by ionizing radiation

“…Table 2 shows the intensity values for the 4p-4s transitions of Ar atoms in Ar and in Ar mixtures with Xe and Kr based on data from Abramov et al (2006). As can be seen from the table, on the addition of 1 kPa of Kr, the line intensity decreases 1.5-fold, and on the addition of Xe, it is halved.…”

“…(1) at k = 2 × 10 −10 cm 3 s −1 , β = 10 −6 cm 3 s −1 and a gas ionization rate S = 10 19 cm −3 s −1 we obtain the impurity pressure at which the transition intensity in the case of the recombination mechanism for level population is halved: Р = 1.6 × 10 16 cm −3 ≈ 60 Pa. Abramov et al (2006) and (Gorbunov et al, 2004) measured luminescence spectra of inert gases and their mixtures under pumping by 235 U fission fragments; the pumping power was 40 W cm −3 , which corresponds to a gas ionization rate of 10 19 cm −3 s −1 . Table 2 shows the intensity values for the 4p-4s transitions of Ar atoms in Ar and in Ar mixtures with Xe and Kr based on data from Abramov et al (2006).…”

“…The absence of 4s-3p transition lines in high-pressure mixtures (Poletaev et al, 1992) is connected with the location of this transition in the IR region of the spectrum, beyond the sensitivity limit of photomultipliers. In the work of Abramov et al (2006), where measurements were made up to 1100 nm, in the excitation of Ne and He-Ne mixture by uranium fission fragments, there is a line at 966.5 nm corresponding to the 4s[3/2] 2 -3p[1/2] 1 transition. Abramov et al (2006) also identified more than 10 lines of the 3d-3p transitions.…”

“…In the work of Abramov et al (2006), where measurements were made up to 1100 nm, in the excitation of Ne and He-Ne mixture by uranium fission fragments, there is a line at 966.5 nm corresponding to the 4s[3/2] 2 -3p[1/2] 1 transition. Abramov et al (2006) also identified more than 10 lines of the 3d-3p transitions. In these transitions, it is mainly the lowest three 3p levels that are populated.…”

“…Similar conclusions may be drawn in relation to the 5p-5s transitions of Kr. The intensities of the Kr lines are given in Table 3, which is also based on data from Abramov et al (2006).…”