The paper deals with a generic problem of collisionless plasma expansion into vacuum in theregimes where the expanding plasma consists of hot electrons and cold ions. The expansion iscaused by electron pressure and serves as an energy transfer mechanism from electrons to ions. Thisprocess is often described under the assumption of Maxwellian electrons, which easily fails in theabsence of collisions. The paper discusses two systems with a naturally occurring non-Maxwelliandistribution: an expanding laser-irradiated nanoplasma and a supersonic jet coming out of amagnetic nozzle. The presented rigorous kinetic description demonstrates how the deviation fromthe Maxwellian distribution fundamentally alters the process of ion acceleration during plasmaexpansion. This result points to the critical importance of a fully kinetic treatment in problems withcollisionless plasma expansion.
展开▼
