RT Conference Proceedings T1 One-dimensional direct Vlasov simulations of non-stationary plasma expansion in magnetic nozzle A1 Sánchez Arriaga, Gonzalo A1 Zhou, Jiewei A1 Ahedo Galilea, Eduardo Antonio A1 Martínez-Sánchez, Manuel A1 Ramos, Jesús José AB The one-dimensional (paraxial approximation) transient expansion into vacuum of a collisionless electron-ion plasma guided by a magnetic nozzle is studied numerically. The simulation box, initially empty, has zero boundary conditions for the gyrocenter distribution functions of electrons and ions fe and fi, except at the entry of the nozzle, where particles with a positive axial velocity follow a Maxwellian. The time evolutions of fe and fi are computed with a parallelized direct Vlasov code, which solves a non-stationary guiding center equation for fully magnetized plasmas and discretizes the distribution functions in phase space. The latter involves the (conserved) magnetic moment, and the axial coordinate and velocity of the particles. The gyrocenter distribution functions of the electrons and the ions, aected by the axial components of the electrostatic electric eld and the gradient of the magnetic eld strength, are coupled through Poisson equation in the code. The evolution of macroscopic quantities, like particle density and electrostatic potential proles, are discussed. Relevant kinetic features, such as the evolution of the ions towards a mono-energetic distribution function and the evolution of the plasma temperature proles, are analyzed. The electron trapping, which the stationary models cannot determined self-consistently, and the transient trapping mechanism are captured by the code. This allows an assessment of the impact of the population of trapped electrons and a detailed analysis of their distribution function in terms of axial position, velocity and magnetic moment. Extensions of the code to two-dimensional congurations with axisymmetric geometry, but still fully magnetized plasmas, are discussed. YR 2017 FD 2017 LK https://hdl.handle.net/10016/27760 UL https://hdl.handle.net/10016/27760 LA eng NO Proceeding of: 35th International Electric Propulsion Conference (IEPC) NO G.S-A was supported by the Ministerio de Economía y Competitividad of Spain (Grant RYC-2014-15357).J.Z. was supported by Airbus DS (Grant CW240050). J.R. and M.M-S stays at UC3M for this research were supported by a UC3M-Santander Chair of Excellence and by National R&D Plan (Grant ESP2016-75887), respectively. E.A. was supported by the MINOTOR project, that received funding from the European Union's Horizon 2020 research and innovation programme, under grant agreement 730028. DS e-Archivo RD 1 jul. 2024