Measurement of anisotropic plasma properties along the magnetic nozzle expansion of an electron cyclotron resonance thruster

Abstract

This work presents experimental measurements along the magnetized plume of the ECR thruster developed by ONERA. Langmuir probes are used to determine the electron energy probability function (eepf) at different axial positions, revealing the non-local character of the distributions. The second part of the paper details a combined diagnostics of non-intrusive diamagnetic loop measurements and laser induced fluorescence to estimate the perpendicular electron temperature inside the plasma source. Averaged perpendicular electron pressure, plasma density, ion velocity at the exit plane and perpendicular electron temperature are determined as functions of the mass flow rate.