Incoherent Thomson scattering measurements of electron properties in a conventional and magnetically-shielded Hall thruster
Benjamin Vincent, Sédina Tsikata, Stéphane Mazouffre
Abstract
Abstract Reliable measurements of electron properties are key for the validation of simulations of Hall thrusters and similar plasma sources. In this paper, a recently-developed incoherent Thomson scattering diagnostic is successfully applied to electron property measurement in a low-power Hall thruster discharge. Investigations of electron properties along radial and azimuthal directions in both conventional and magnetically-shielded architectures are performed. The high diagnostic sensitivity gives access to electron property measurements in a plasma environment with densities as low as <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msup> <mml:mrow> <mml:mn>10</mml:mn> </mml:mrow> <mml:mrow> <mml:mn>16</mml:mn> </mml:mrow> </mml:msup> <mml:mspace width="0.25em"/> <mml:msup> <mml:mrow> <mml:mi mathvariant="normal">m</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>3</mml:mn> </mml:mrow> </mml:msup> </mml:math> . Electron temperatures reaching several tens of eV and drift velocities on the order of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:msup> <mml:mrow> <mml:mn>10</mml:mn> </mml:mrow> <mml:mrow> <mml:mn>6</mml:mn> </mml:mrow> </mml:msup> <mml:mspace width="0.25em"/> <mml:msup> <mml:mrow> <mml:mrow> <mml:mi mathvariant="normal">m</mml:mi> </mml:mrow> <mml:mspace width="0.25em"/> <mml:mrow> <mml:mi mathvariant="normal">s</mml:mi> </mml:mrow> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>3</mml:mn> </mml:mrow> </mml:msup> </mml:mrow> </mml:math> are measured in the exit plane region. The impact of the magnetic field (intensity and direction) and discharge voltage are investigated.