Laser-induced fluorescence measurements of velocity within a Hall discharge

Abstract

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Optical Boron Nitride Insulator Erosion Characterization of a 200 W Xenon Hall Thruster

“…Previous measurements have shown that the length over which ions are accelerated within a Hall thruster does not vary with discharge potential [4]. Increases in the discharge potential directly translate into increases in the average electric field within the ion acceleration region.…”

“…The only operational difference is that power was not supplied to the heater, or keeper. The spectroscopy and LIF measurement techniques are described more fully elsewhere [3][4]. A New Focus Vortex tunable diode laser, capable of tuning approximate ±50 GHz about a center wavelength of 834.7 nm, is used for these measurements.…”

Laser-Induced Fluorescence of Neutral Xenon in the Near Field of a 200 W Hall Thruster

“…The xenon transition used in this study is optically accessible using relatively inexpensive diode lasers and is approximately 17 GHz from the ionic transition previously used to measure xenon ion velocities [1,6]. Although not all transition spectral constants are known for either transi- …”

“…This interaction leads to the splitting of levels with angular momentum into a number of components, each corresponding to a specific value of the total angular momentum . The details of how hyperfine spin splitting affects the spectra of xenon are described in more detail elsewhere [1].…”

Measurement of XeI and XeII velocity in the near exit plane of a low-power Hall effect thruster by light induced fluorescence spectroscopy

“…It is worth pointing out the unparalleled properties of the LIF velocimetry, which is very unintrusive, has high spatial resolution, offers the possibility to extract information even where the plasma itself is created, is species selective, and permits the simultaneous detection of multiple velocity components. Excellent results have been obtained with LIF-based techniques in various types of electric thrusters, with reference to the 6 kW power range [1,2], the 1 kW range [3,4] and low to medium power range [5][6][7].…”