Relaxation 1D magnetized, collisionless plasma systems

One-dimensional magnetized plasma systems are ubiquitous in the Universe. In Cartesian geometry, magnetic field reversals and current sheets are abundant in planetary magnetospheres and solar wind turbulence. In cylindrical geometry, flux tubes and flux ropes are present as solar coronal loops and astrophysical jets. Although these systems are often regarded as equilibrium solutions, in reality they are more likely to start from disequilibrated states. Here we present the relaxation process of such magnetized, collisionless plasma systems, by classifying single-particle orbits and analyzing phase-space particle dynamics. The process is verified by particle-in-cell simulations and comparisons to spacecraft observations.