Quasistatic Magnetic Field Generation by an Intense Ultrashort Laser Pulse in Underdense Plasma

The quasistatic magnetic field created in the interaction of intense ultrashort laser pulses with underdense plasmas has been investigated by two-dimensional particle simulation.The relativistic ponderomotive force and plasma wave excited in self-modulation processes can drive intense electron current mainly in the propagation direction.As a result,an azimuthal,multi-mega Gauss order quasi-static magnetic field can be generated around the laserbeam.

Characterization of Pattern Formation from Modulation Instability in the Cubic Schrodinger Equation

The study of pattern dynamics in a Hamiltonian system(HS)having an infinite number of degree of freedom is very difficult due to the absence of attractors in such system.In this letter,we propose a useful method that only a few representative manifolds in phase space are investigated,and it can be used to reveal the pattern formation of HS.The conserved cubic Schrödinger equation is discussed.Although a special model is chosen,this method can be applied to more general case such as the near-integrable HS.

Bursting behaviours in cascaded stimulated Brillouin scattering

Stimulated Brillouin scattering is studied by numerically solving the Vlasov Maxwell system. A cascade of stim- ulated Brillouin scattering can occur when a linearly polarized laser pulse propagates in a plasma. It is found that a stimulated Brillouin scattering cascade can reduce the scattering and increase the transmission of light, as well as intro- duce a bursting behaviour in the evolution of the laser-plasma interaction. The bursting time in the reflectivity is found to be less than half the ion acoustic period. The ion temperature can affect the stimulated Brillouin scattering cascade, which can repeat several times at low ion temperatures and can be completely eliminated at high ion temperatures. For stimulated Brillouin scattering saturation, higher-harmonic generation and wave wave interaction of the excited ion acoustic waves can restrict the amplitude of the latter. In addition, stimulated Brillouin scattering cascade can restrict. the amplitude of the scattered light.

Dipole AlfvenVortex with Finite Ion Larmor Radius in a Low-Beta Plasma

A set of nonlinear fluid equations which include the effects of ion gyroradius is derived to describe Alfven vortex. The correction of finite ion gyroradius to the Alfven vortex in the inertial region is much more significant than that in the kinetic region. The amplitude of the vortex is enhanced in both regions. The scale of the vortex in the kinetic region becomes larger whereas it becomes smaller in the inertial region.

Design of an Indirect-Drive Pulse Shape for ~1.6 MJ Inertial Confinement Fusion Ignition Capsules

We present a design of indirect-drive pulse shape for inertial confinement fusion ignition capsules using laser energy 1.6 MJ with a moderate gain （~10） on the Shenguang 1V laser facility. The trade-off fuel compression （pressure） for resistance to the hydrodynamic instability （HI） in the recent high-foot （HF） implosion campaign [Dittrieh T t et al Phys. Rev. Lett. 112 （2014）055002] is recovered. The proposed design modifies the ＂main＂ pulse shape, which features a decompression-recompression step for the fuel shell resulting in higher areal density than that of the ＂simple＂ HF design, and thereby approaches the conditions required for ignition avoiding at the expense of more laser energy while holding the HI under control.