Diode Laser-Induced Fluorescence of Xenon Ion Velocity Distributions

We present preliminary results from optogalvanic and laser-induced fluorescence (LIF) measurements of the nuclear-spin and isotopic structure of the 5d 2 F 7/2 → 6p 2 D 0 5/2 transition of singly-ionized xenon (Xe II) at 834.7 nm.Ion velocity distributions deconvolved from 5d 4 D 7/2 → 6p 4 P 0 5/2 optogalvanic spectra at 605.1 nm provided the Doppler broadening function for a computational model of the 834.7 nm absorption line.Ensemble averaging of optogalvanic spectra taken at 834.7 nm provided an experimental data set for estimation of the unknown isotopic shifts and lower-state (5d 2 F 7/2 ) nuclear-spin constants via a conjugate-gradient optimization routine.Deconvolution of 834.7 nm LIF spectra with the newly-modeled 834.7 nm cold-plasma spectrum returned an unusually broad velocity distribution, rather than the expected kinematic cooling effect.Comparison of a deconvolved ion energy distribution taken in a 500 V ion beam with retarding potential analyzer data showed bulk ion energy agreement within 1%, but only qualified similarity between the distributions.Grid misalignment during the LIF experiment may be responsible for the usually broad Doppler broadening.As a result, we are presently unable to reliably validate our deconvolution method at 834.7 nm.