A pulsed source for Xe(6s[3/2]1) and Xe(6s′[1/2]1) resonance state atoms using two-photon driven amplified spontaneous emission from the Xe(6p) and Xe(6p′) states

Abstract

A new, simple method for the generation of Xe(6s[3/2]1) and Xe(6s′[1/2]1) atoms is described. The method involves resonant two-photon excitation of Xe(6p[1/2]0 and 6p′[3/2]2) states followed by amplified spontaneous emission (ASE) to the Xe(6s[3/2]1 and 6s′[1/2]1) states. The vacuum ultraviolet transitions, Xe(6s[3/2]1→5p6(1S0)) at 147 nm and Xe(6s′[1/2]1→5p6(1S0)) at 129.6 nm, were used to monitor the time dependence of the resonance state atom concentrations. The quenching rate constants of these resonance atoms with ten molecules were measured at 300 K. The quenching cross-sections of the Xe(6s and 6s′) resonance atoms are compared to the cross-sections of the metastable Xe(6s[3/2]2) atoms and Xe(6p[3/2]2) atoms. The correlation between quenching cross-sections and photoabsorption cross-section of the molecules predicted by the resonance dipole–dipole energy transfer model is discussed. The applicability of the two-photon driven ASE method for the generation of other resonance state atoms is considered.

Optimization of a Dielectric Barrier Discharge for Pulsed UV Emission of XeCl at 308 nm

“…HCl has large cross sections for dissociative electron attachment [33] that produces chlorine ions and supports reactions 2 and 3. Cl 2 is a favourable donor in case of the harpoon reaction 1 because then XeCl is the main quenching product of metastable xenon atoms by Cl 2 in contrast to other chlorine containing molecules [34][35][36]. To clarify this question in our experimental condition, we will consider our measured decay times in more detail.…”

“…The data obtained for different Cl 2 content in both lamps with gas gaps of 2.5 mm and 6.5 mm, respectively coincide in the range of the experimental error and can be described by a straight line with a slope of (4.6 ± 0.5) ·10 −10 cm 3 s −1 . The rate coefficient of harpoon reaction has been measured with two independent experimental techniques [35,36] and is known with high precision to k=(6.9 ± 0.4) ·10 −10 cm 3 s −1 . A more detailed view on figure 5(d) also indicates that fitted line has a small positive value at zero Cl 2 densities which contradicts to eq.…”

The influence of amplified spontaneous emission in collisional energy transfer studies exemplified by to transfer in I2

“…However, removing ASE by reducing the laser powers alone proved to be difficult, as observed in the earlier atomic studies [9,10]. Thirdly, the length of the cell can be reduced; an approach that was used by Alekseev and Setser [9,10]. In their one-colour atomic studies the length of the cell defined the path length, L in Eq.…”

“…For any given transition, Eq. (1) suggests several approaches to the reduction or elimination of ASE by the failure to achieve the critical concentration and these were outlined by Alekseev and Setser [9,10].…”

“…Previously, it was shown how ASE transfer can influence the results of collisional studies of excited atoms and how the experimental arrangement could be adapted in order to eliminate it [9][10][11]. In spite of these findings, ASE has generally not been considered as a possible alternative transfer route from the initial to final state in collisional studies of excited molecules.…”