Kinetic modelling of plasma parallel transport in open systems with Ion Cyclotron Radio-frequency and Neutral beam heating scenarios*

In this work, the hybrid Particle-In-Cell code: PICOS++ ^[1] is applied to study plasma transport in two different open magnetic geometries. The analyses include the effects of: (1) finite fully-absorbing boundaries for the particles, (2) volumetric particle sources, (3) Fokker-Plank Collision operator and (4) Radio-Frequency (RF) heating. RF heating on a divertor simulator: Material Plasma Exposure eXperiment (MPEX) is studied to understand ion heating using fundamental ion cyclotron resonance and its associated parallel transport. Calculations show that RF heating creates ion temperature anisotropy and strongly modifies the plasma density and parallel flow leading to significant drop in density near the target region. This density drop near the target in MPEX is found to saturate with higher RF power.  Furthermore, the effect of Neutral Beam Injection (NBI) on the parallel electric field and plasma confinement in an Axisymmetric Magnetic mirror geometry has been investigated. It is found that the presence of NBI enhances the confinement of warm ions in a mirror plasma system. A sensitivity scan of source temperature, neutral beam energy, mirror ratio and mirror length are also performed to study their impact on plasma confinement time in mirror geometry.