Laser plasma simulations of the generation processes of Alfven and collisionless shock waves in space plasma

18th International Conference PhysicA.SPb

Prokopov, P.A.^1 ; Zakharov, Yu.P.^1 ; Tishchenko, V.N.^1 ; Shaikhislamov, I.F.^1 ; Boyarintsev, E.L.^1 ; Melekhov, A.V.^1 ; Ponomarenko, A.G.^1 ; Posukh, V.G.^1 ; Terekhin, V.A.^2

Institute of Laser Physic (ILP) SB RAS, Av. Lavrentyeva 13/3, Novosibirsk

630090, Russia^1

All-Russian Scientific Research Institute for Experimental Physics (VNIIEF), Av. Mira 37, Sarov

607188, Russia^2

关键词: Azimuthal magnetic fields;    Diamagnetic cavities;    External magnetic field;    Induction electric fields;    Interaction parameters;    Strong perturbations;    Structure and dynamics;    Transverse perturbation;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/769/1/012086/pdf
DOI  :  10.1088/1742-6596/769/1/012086

来源: IOP

【 摘 要 】

Generation of Alfven waves propagating along external magnetic field B0and Collisionless Shock Waves propagating across B0are studied in experiments with laser- produced plasma and magnetized background plasma. The collisionless interaction of interpenetrating plasma flows takes place through a so-called Magnetic Laminar Mechanism (MLM) or Larmor Coupling. At the edge of diamagnetic cavity LP-ions produce induction electric field Eφwhich accelerates BP-ions while LP-ions rotate in opposite direction. The ions movement generates sheared azimuthal magnetic field Bφwhich could launches torsional Alfven wave. In previous experiments at KI-1 large scale facility a generation of strong perturbations propagating across B0with magnetosonic speed has been studied at a moderate value of interaction parameter δ∼0.3. In the present work we report on experiments at conditions of 5∼R2 and large Alfven-Mach number MA∼10 in which strong transverse perturbations traveling at a scale of ∼1 m in background plasma at a density of ∼3∗1013cm-3is observed. At the same conditions but smaller MA∼ 2 a generation, the structure and dynamic of Alfven wave with wavelength ∼0.5 m propagating along fields B0∼100500 G for a distance of ∼2.5 m is studied.