Collisionless shock generation in high-speed counterstreaming plasma flows by a high-power laser

Abstract

The experimental demonstration of the formation of a strong electrostatic (ES) collisionless shock has been carried out with high-speed counterstreaming plasmas, produced by a high-power laser irradiation, without external magnetic field. The nearly four times density jump observed in the experiment shows a high Mach-number shock. This large density jump is attributed to the compression of the downstream plasma by momentum transfer by ion reflection of the upstream plasma. Particle-in-cell (PIC) simulation shows the production of a collisionless high Mach-number ES shock with counterstreaming interaction of two plasma slabs with different temperatures and densities, as pointed out by Sorasio et al. [Phys. Rev. Lett. 96, 045005 (2006)]. It is speculated that the shock discontinuity is balanced with the momentum of incoming and reflected ions and the predominant pressure of the electrons in the downstream with PIC simulation.

Laboratory astrophysics with laser-driven strong magnetic fields in China

“…Counter-streaming plasmas system is a test bed for studying such phenomena in laboratory [27] . Previous SG-II experiments have successfully generated shock wave using unmagnetized counter-streaming plasmas [28][29][30] . In order to generate magnetized plasmas to study the shock wave driven by the CMEs, we plan to add a kilo-Tesla level magnetic field induced by the capacitor-coil target [18] into the counterstreaming plasmas system.…”

High Mach-number collisionless shock driven by a laser with an external magnetic field

“…We have studied collisionless shocks with high-power laser-produced counter-streaming plasmas [3,4]. A large density jump due to an electrostatic (ES) shock has been observed by the optical diagnostics such as shadowgraphy (SG) and interferometry (IF) [3]. Using streaked optical pyrometry (SOP) and streaked interferometry (SIF), time evolution of high Mach-number ES shocks has been observed [4].…”

“…We have studied collisionless shocks with high-power laser-produced counter-streaming plasmas [3,4]. A large density jump due to an electrostatic (ES) shock has been observed by the optical diagnostics such as shadowgraphy (SG) and interferometry (IF) [3].…”

Formation of counterstreaming plasmas for collisionless shock experiment

“…A bow shock has been generated by placing a solid obstacle in the path of a high-velocity laser ablation plasma [4]. Formation of high-Mach number collisionless electrostatic shock wave in counterstreaming plasmas using a double-plane target has been reported [6,7]. It is essential to generate the plasmas that a e-mail: kuramitsu-y@ile.osaka-u.ac.jp This is an Open Access article distributed under the terms of the Creative Commons Attribution License 2.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.…”

“…Recently, experimental researches have been carried out using high power laser systems [4][5][6][7]. A bow shock has been generated by placing a solid obstacle in the path of a high-velocity laser ablation plasma [4].…”