title: Calibrating ion density profile measurements in ion thruster beam plasma.
abstract: The ion thruster beam plasma is characterized by high directed ion velocity (104m/s) and low plasma density (1015m-3). Interpretation of measurements of such a plasma based on classical Langmuir probe theory can yield a large experimental error. This paper presents an indirect method to calibrate ion density determination in an ion thruster beam plasma using a Faraday probe, a retarding potential analyzer, and a Langmuir probe. This new method is applied to determine the plasma emitted from a 20-cm-diameter Kaufman ion thruster. The results show that the ion density calibrated by the new method can be as much as 40% less than that without any ion current density and ion velocity calibration.
authors.affiliation: School of Astronautics, Beihang University, Beijing 100191, China.
authors.forename: Zun
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: School of Astronautics, Beihang University, Beijing 100191, China.
authors.forename: Haibin
authors.initials: H
authors.lastname: Tang
authors.affiliation: School of Astronautics, Beihang University, Beijing 100191, China.
authors.forename: Junxue
authors.initials: J
authors.lastname: Ren
authors.affiliation: School of Astronautics, Beihang University, Beijing 100191, China.
authors.forename: Zhe
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Department of Astronautical Engineering, University of Southern California, Los Angeles, California 90089, USA.
authors.forename: Joseph
authors.initials: J
authors.lastname: Wang