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Collisionless shocks are produced in counter-streaming plasmas with an external magnetic field. The shocks are generated due to an electrostatic field generated in counter-streaming laser-irradiated plasmas, as reported previously in a series of experiments without an external magnetic field [T. Morita et al., Phys. Plasmas, 17, 122702 (2010), Kuramitsu et al., Phys. Rev. Lett., 106, 175002 (2011)] via laserirradiation of a double-CH-foil target. A magnetic field is applied to the region between two foils by putting an electro-magnet (~10 T) perpendicular to the direction of plasma expansion. The generated shocks show different characteristics later in time (t > 20 ns). [ABSTRACT FROM AUTHOR]

The experiments to simulate astrophysical jet generation are performed using Gekko XII (GXII) HIPER laser system at the Institute of Laser Engineering. In the experiments a fast plasma flow generated by shooting a CH plane (10 µm thickness) is observed at the rear side of the plane. By separating the focal spot of the main beams, a non-uniform plasma is generated. The non-uniform plasma flow in an external magnetic field (0.2~0.3 T) perpendicular to the plasma is more collimated than that without the external magnetic field. The plasma β, the ratio between the plasma and magnetic pressure, is » 1, and the magnetic Reynolds number is ~150 in the collimated plasma. It is considered that the magnetic field is distorted by the plasma flow and enhances the jet collimation. [ABSTRACT FROM AUTHOR]

A collisionless Weibel-instability mediated shock in a self-generated magnetic field is studied using two-dimensional particle-in-cell simulation [Kato and Takabe, Astophys. J. Lett. 681, L93 (2008)]. It is predicted that the generation of the Weibel shock requires to use NIF-class high-power laser system. Collisionless electrostatic shocks are produced in counter-streaming plasmas using Gekko XII laser system [Kuramitsu et al., Phys. Rev. Lett. 106, 175002 (2011)]. A NIF facility time proposal is approved to study the formation of the collisionlessWeibel shock. OMEGA and OMEGA EP experiments have been started to study the plasma conditions of counter-streaming plasmas required for the NIF experiment using Thomson scattering and to develop proton radiography diagnostics. [ABSTRACT FROM AUTHOR]