Measurement of Aluminum Erosion Rate by Cavity Ring-Down Spectroscopy

Boron Nitride Sputter Erosion Measurements by Cavity Ring-Down Spectroscopy

Sputter erosion is a critically important process in many electric propulsion (EP) devices from the point of view of both lifetime assessment and contamination effects. In many Hall thrusters erosion of boron nitride (BN) is of primary interest. In this contribution we introduce the use of cavity ring-down spectroscopy (CRDS) as a diagnostic for measurement of sputtered BN. The measurement appr...

Cavity-locked ring-down spectroscopy

High-Sensitivity Boron Nitride Sputter Erosion Measurements by Continuous-Wave Cavity Ring-Down Spectroscopy

Sputter erosion of boron nitride (BN) plays a key life-limiting role in many Hall thrusters. We report on the development of cavity ring-down spectroscopy (CRDS) as a sensitive and accelerated diagnostic for sputter erosion. The measurement approach is based upon probing sputtered boron atoms in the region of 250 nm. We present quantitative detection of sputtered BN using CRDS with a pulsed las...

Erosion Measurements by Cavity Ring-Down Spectroscopy for the VHITAL Program

We report the use of cavity ring-down spectroscopy (CRDS) as a diagnostic tool to study sputter erosion of the VHITAL (Very High Isp Thruster with Anode Layer) thruster. The lifetime of the VHITAL thruster is largely governed by sputter erosion of guard-rings and other critical components. The CRDS technique will be used to measure sputtered molybdenum in the plume of the thruster for various t...

Saturated-absorption cavity ring-down spectroscopy.

We report on a novel approach to cavity ring-down spectroscopy with the sample gas in saturated-absorption regime. This technique allows us to decouple and simultaneously retrieve the empty-cavity background and absorption signal, by means of a theoretical model that we developed and tested. The high sensitivity and frequency precision for spectroscopic applications are exploited to measure, fo...