2016 Volume 14 Issue ists30 Pages Pb_111-Pb_116
A cavity ring-down spectroscopy method to measure sputter erosion and estimate the lifetime of electric propulsion systems was developed. We measured sputtered aluminum atoms from the acceleration grid of an ion thruster. An external-cavity diode laser was used as the probe laser to measure the aluminum transition line from ground state to upper state, at 394.512 nm (vacuum). The erosion rate of the acceleration grid was estimated to be 259 ± 99 ng/s.