Rotational and vibrational temperatures of molecular hydrogen in a hollow cathode glow discharge

Abstract

Optical emission spectroscopy is used for the determination of hydrogen molecule rotational T rot and vibrational T vib and translational temperature T tr . The experiment was carried out using copper or titanium hollow cathode discharges operated in pure hydrogen. The rotational temperature of excited electron energy levels is determined from Fulcher-α diagonal bands (d 3 u → a 3 + g electronic transition, P-, Q-and R-branches), which were later used to derive the rovibronic temperature of the hydrogen molecule ground state, which is assumed equal to T tr . The vibrational temperature T vib is determined for the same electronic transition (Q-branch with ν = 2,3; ν = 0). For all temperatures the radial temperature distribution is reported.

Quantitative determination of mass-resolved ion densities in H2-Ar inductively coupled radio frequency plasmas

“…The upper level is assumed to be populated only by direct electron excitation from the electronic ground state X 1 Σ + g with v = 0 which does not change the rotational distribution. This condition is satisfied in low-pressure discharges 53,54 . The rotational distribution of the ground state is assumed to be thermally populated due to collisions with other gas particles.…”

The use of hollow cathodes in deposition processes: A critical review

“…An extensive review of the published work on hydrogen discharges in a hollow cathode [167][168][169][170][171] shows that many studies have involved high-density discharges in a D-HC hollow cathode, but we have not found any report that unmistakeably demonstrates the existence of a quasi-resonant HCD state using pure hydrogen.…”

Measurement of C2 and CH temperatures in argon‐acetylene low‐pressure microwave‐induced plasma

“…[16] Due to rotational terms Λ-type doubling and according to selection rules, [16] 16 main branches of the 3 Π-3 Π transition are possible-P i (J) (i = 1,2,3), R i (J) (i = 1,2,3), and Q i (J) (i = 2,3) i.e. 3 The temperature measurement procedure A detailed description of the rotational temperature determination is given in Majstorović et al [20] and hence only minimum details will be given here. Apart from these branches, the satellite bands like e.g.…”