Kinetics of Rb formation from RbCl in the positive column of the hydrogen-pulsed discharge

Time transients of the number densities of Rb in the ground electronic state were measured in a positive column of moderate-current hydrogen-pulsed discharge. Atomic rubidium was formed by dissociation of RbCl. The population of Rb was monitored by high resolution laser absorption. The laser was tuned to one of the D2 transitions near 780 nm. Experiments were done at hydrogen number densities from 6.4 × 1015 to 9.6 × 1016 cm−3 and current densities ranging from 0.1 to 0.5 A cm−2. Number densities of RbCl varied from 4.0 × 105 to 3.0 × 107 cm−3. The kinetic model in the form of rate equations reproduces closely measured time transients of the Rb population. The model assumes that the primary mechanism for the production of atomic rubidium is the chemical reaction RbCl + H → Rb + HCl.