2010/03/01 by N. Shimada, Nobue Shimada, Masahiro Hoshino +3 · 2 citations
Physics and Astronomy · #Astrophysical plasma #Astrophysics and Cosmic Phenomena #Dissipation #Electron #Gyroradius #Ion #Ionosphere and magnetosphere dynamics #Laser-Plasma Interactions and Diagnostics #Magnetic field #Shock (circulatory) #Shock wave #Shock waves in astrophysics #Supernova #astro-ph.HE #astro-ph.SR
paper · pdf · doi:10.1063/1.3322828
published in Physics of Plasmas 17(3), 032902 (American Institute of Physics) · 30 pages, 11 figures
openalex publication_date 2010/03/01 · arxiv created 2010/04/16 · arxiv updated 2010/04/19 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
A new rapid energization process within a supernova shock transition region (STR) is reported by utilizing numerical simulation. Although the scale of a STR as a main dissipation region is only several hundreds of thousands km, several interesting structures are found relating to generation of a root of the energetic particles. The nonlinear evolution of plasma instabilities lead to a dynamical change in the ion phase space distribution which associates with change of the field properties. As a result, different types of large-amplitude field structures appear. One is the leading wave packet and another is a series of magnetic solitary humps. Each field structure has a microscopic scale (~ the ion inertia length). Through the multiple nonlinear scattering between these large-amplitude field structures, electrons are accelerated directly. Within a STR, quick thermalization realizes energy equipartition between the ion and electron, hot electrons play an important role in keeping these large-amplitude field structures on the ion-acoustic mode. The hot electron shows non-Maxwellian distribution and could be the seed of further non-thermal population. The "shock system", where fresh incoming and reflected ions are supplied constantly, play an essential role in our result. With a perpendicular shock geometry, the maximum energy of the electron is estimated by equating a width of the STR to a length of the Larmor radius of the energetic electron. Under some realistic condition of MA = 170 and ωpe/Ωce = 120, maximum energy is estimated to ~ 10 MeV at an instant only within the STR.