Competition among the two-plasmon decay (TPD) of backscattered light of stimulated Raman scattering (SRS), filamentation of the electron-plasma wave (EPW) and forward side SRS is investigated by two-dimensional particle-in-cell simulations. Our previous work [K. Q. Pan et al., Nucl. Fusion 58, 096035 (2018)] showed that in a plasma with the density near 1/10 of the critical density, the backscattered light would excite the TPD, which results in suppression of the backward SRS. However, this work further shows that when the laser intensity is so high ( $>{10}^{16}$ W/cm²) that the backward SRS cannot be totally suppressed, filamentation of the EPW and forward side SRS will be excited. Then the TPD of the backscattered light only occurs in the early stage and is suppressed in the latter stage. Electron distribution functions further show that trapped-particle-modulation instability should be responsible for filamentation of the EPW. This research can promote the understanding of hot-electron generation and SRS saturation in inertial confinement fusion experiments.

介绍了以强激光驱动电容线圈靶的实验方法产生磁场的基本模型及其发展过程。对比了实验室中常用的三种磁场诊断方法，包含：B-dot、法拉第旋转以及质子背光，发现前两种方法在实验中仅可以获得距离靶较远处的有限个磁场值，通过结合模拟工具获得靶处的磁场值与测量点的值跨越几个数量级，容易产生误差；质子背光诊断可以在实验中获得全局磁场信息，能够较好地满足线圈靶磁场诊断的需求。由于线圈靶磁场强且可持续时间长，在时空分布上具有一定可控性，因此我们将其应用到了磁重联的研究中，并成功获得了重联出流等特征。另外线圈靶在带电粒子的约束和磁流体动力学研究等多方面也得到了应用。

激光聚变有望一劳永逸地解决人类的能源问题，因而受到国际社会的普遍重视，一直是国际研究的前沿热点。目前实现激光惯性约束聚变所面临的最大科学障碍（属于内禀困难）是对内爆过程中高能量密度流体力学不稳定性引起的非线性流动的有效控制，对其研究涵盖高能量密度物理、等离子体物理、流体力学、计算科学、强冲击物理和高压原子物理等多个学科，同时还要具备大规模多物理多尺度多介质流动的数值模拟能力和高功率大型激光装置等研究条件。作为新兴研究课题，高能量密度非线性流动问题充满了各种新奇的现象亟待探索。此外，流体力学不稳定性及其引起的湍流混合，还是天体物理现象（如星系碰撞与合并、恒星演化、原始恒星的形成以及超新星爆炸）中的重要过程，涉及天体物理的一些核心研究内容。本文首先综述了高能量密度非线性流动研究的现状和进展，梳理了其中的挑战和机遇。然后介绍了传统中心点火激光聚变内爆过程发生的主要流体力学不稳定性，在大量分解和综合物理研究基础上，凝练出了目前制约美国国家点火装置（NIF）内爆性能的主要流体不稳定性问题。接下来，总结了国外激光聚变流体不稳定性实验物理的研究概况。最后，展示了内爆物理团队近些年在激光聚变内爆流体不稳定性基础性问题方面的主要研究进展。该团队一直从事激光聚变内爆非线性流动研究与控制，以及聚变靶物理研究与设计，注重理论探索和实验研究相结合，近年来在内爆重要流体力学不稳定性问题的解析理论、数值模拟和激光装置实验设计与数据分析等方面取得了一系列重要成果，有力地推动了该研究方向在国内的发展。

基于脉冲功率技术的箍缩装置能够在cm空间尺度和百ns时间尺度产生极端的高温、高压、高密度以及强辐射环境。中物院流体物理研究所在已建成的10 MA级的大型箍缩装置上开展多种负载构型的高能量密度物理实验研究。利用Z箍缩动态黑腔创造出了惯性约束聚变研究所需的高温辐射场；研究了金属箔套筒和固体套筒的内爆动力学特性；利用中低Z材料内爆获得了可观的K壳层线辐射并用于X射线热-力学效应实验研究；磁驱动准等熵加载和冲击加载为材料动态特性研究提供了新的实验能力；采用环形二极管和反射三极管技术的轫致辐射源获得了高剂量（率）的X射线和γ射线；利用磁驱动的径向金属箔模拟了天体物理中恒星射流的形成及其辐射的产生。此外，还介绍了利用反场构型磁化靶聚变装置开展的预加热磁化等离子体靶形成等实验结果。

We report on the design and first results from experiments looking at the formation of radiative shocks on the Shenguang-II (SG-II) laser at the Shanghai Institute of Optics and Fine Mechanics in China. Laser-heating of a two-layer CH/CH–Br foil drives a $\sim 40$ km/s shock inside a gas cell filled with argon at an initial pressure of 1 bar. The use of gas-cell targets with large (several millimetres) lateral and axial extent allows the shock to propagate freely without any wall interactions, and permits a large field of view to image single and colliding counter-propagating shocks with time-resolved, point-projection X-ray backlighting ($\sim 20$ μm source size, 4.3 keV photon energy). Single shocks were imaged up to 100 ns after the onset of the laser drive, allowing to probe the growth of spatial nonuniformities in the shock apex. These results are compared with experiments looking at counter-propagating shocks, showing a symmetric drive that leads to a collision and stagnation from $\sim 40$ ns onward. We present a preliminary comparison with numerical simulations with the radiation hydrodynamics code ARWEN, which provides expected plasma parameters for the design of future experiments in this facility.

In this paper, we present a reanalysis of the silicon He-$\mathrm{\alpha}$ X-ray spectrum emission in Fujioka et al.’s 2009 photoionization experiment. The computations were performed with our radiative-collisional code, RCF. The central ingredients of our computations are accurate atomic data, inclusion of satellite lines from doubly excited states and accounting for the reabsorption of the emitted photons on their way to the spectrometer. With all these elements included, the simulated spectrum turns out to be in good agreement with the experimental spectrum.

Magnetic reconnection driven by laser plasma interactions attracts great interests in the recent decades. Motivated by the rapid development of the laser technology, the ultra strong magnetic field generated by the laser-plasma accelerated electrons provides unique environment to investigate the relativistic magnetic field annihilation and reconnection. It opens a new way for understanding relativistic regimes of fast magnetic field dissipation particularly in space plasmas, where the large scale magnetic field energy is converted to the energy of the nonthermal charged particles. Here we review the recent results in relativistic magnetic reconnection based on the laser and collisionless plasma interactions. The basic mechanism and the theoretical model are discussed. Several proposed experimental setups for relativistic reconnection research are presented.

基于脉冲功率技术的Z箍缩过程可以实现驱动器电储能到X光辐射的高效率转换，形成极端温度、密度、压力条件，近年来在惯性约束聚变及高能量密度应用中取得了一系列重要进展。综述了国际上辐射间接驱动和磁直接驱动两条Z箍缩聚变技术路线发展现状，简要介绍了我国Z箍缩聚变尤其是7~8 MA脉冲功率装置上的动态黑腔研究进展；分别从辐射与物质相互作用、辐射不透明度、材料动态特性、实验室天体物理等方面，概述了Z箍缩应用于高能量密度物理研究的技术路线和主要成果。希望通过对Z箍缩聚变及高能量密度应用研究的论述和发展趋势分析，推动我国Z箍缩研究领域的进一步发展。

The development of laser performance models having real-time prediction capability for the OMEGA EP laser system has been essential in meeting requests from its user community for increasingly complex pulse shapes that span a wide range of energies. The laser operations model PSOPS provides rapid and accurate predictions of OMEGA EP laser-system performance in both forward and backward directions, a user-friendly interface and rapid optimization capability between shots. We describe the model’s features and show how PSOPS has allowed real-time optimization of the laser-system configuration in order to satisfy the demands of rapidly evolving experimental campaign needs. We also discuss several enhancements to laser-system performance accuracy and flexibility enabled by PSOPS.