RT Journal Article T1 Magnetic Nozzle and RPA Simulatons vs. Experiments for a Helicon Plasma Thruster Plume A1 Cichoki, Filippo A1 Navarro Cavallé, Jaume A1 Modesti, Alberto A1 Ramírez Vázquez, Gonzalo AB The experimental characterization of electrodeless plasma thrusters with a magneticnozzle is fundamental in the process of increasing their maturity to reach theindustrialization level. Moreover, it offers the unique opportunity of validating existingnumerical models for the expansion of a magnetized plasma plume, and for the syntheticsimulation of diagnostics measurements, like those of a retarding potential analyzer, whichprovides essential information regarding the ion beam energy distribution function.Simulations to experiments comparison ultimately enables a better understanding ofthe physical processes behind the observed experimental curves. In this work, inputexperimental data of a Helicon plasma plume is used to simulate both a magnetic nozzleexpansion in the divergent field region, and the corresponding measurements of aretarding potential analyzer, through dedicated small-scale simulations of thisdiagnostics tool. Magnetic nozzle simulation and experimental results agree well interms of the angular distribution of the ion current at 40 cm distance from the source,and also in the prediction of the energies of the two main peaks of the ion energydistribution function: a first one at 45 eV due to source ions, and a second one, at15-20 eV, due to ions from charge-exchange and ionization collisions in the plume. Finally,the small-scale simulation of the retarding potential analyzer permits to assess the parasiticeffects caused by the ion current collected by the different analyzer grids. The inclusion ofthe retarding and electron suppression grids currents in the overall I-V characteristic isshown to correct almost entirely these effects on the obtained ion velocity distribution. PB Frontiers SN 2296-424X YR 2022 FD 2022-04-14 LK https://hdl.handle.net/10016/34575 UL https://hdl.handle.net/10016/34575 LA eng NO This work has been funded by European Union's Horizon 2020research and innovation program under grant agreement No 870542HIPATIA(HelIconPlasmAThruster for In-space Applications), andthe Spanish National research plan under the project ESPEOS,PID2019-108034RB-I00/AEI/10.13039/501100011033. DS e-Archivo RD 27 jul. 2024