Studying impurities in the plasma jet of a closed-electron-drift thruster

A new approach to the real-time diagnostics of the erosion of walls in the discharge chamber of a plasma accelerator (thruster) with closed electron drift (CED) is described. The proposed method is based on the measurement of intensities of (i) the spectral lines of atoms sputtered from the discharge chamber walls and (ii) the reference lines of the neutral working gas component. The rate of erosion of the dielectric walls in a discharge chamber of a CED thruster has been measured for the discharge voltage increased from 300 to 700 V. An experimental relationship is established that takes into account changes in the velocities and charge states of the sputtered species and allows the proposed method to be used for various discharge voltages.