激光间接驱动柱形腔壁辐照特性

在惯性约束聚变间接驱动装置中，针对柱形腔两端注入结构及其光路排布方案，建立了基于束匀滑技术的激光束传输模型。在此基础上，分析了激光集束在真空柱形腔腔壁上的辐照特性，并根据柱形腔整体腔壁光斑排布特性，对激光集束光路排布进行了初步优化。结果表明，随着入射角度的增加，激光集束在腔壁的光斑尺寸逐渐变小，而其在腔壁上的热斑比例无明显变化，偏振特性也基本保持一致。通过进一步分析所有激光集束在腔壁上的强度分布和热斑比例可知，内、外环激光集束在腔壁上的交叠区域将增大局部峰值强度，提高热斑比例。可以通过适当调节内环激光集束的焦面位置和入射角度来改善所有激光集束在腔壁上的辐照特性。

Irradiation characteristics of laser quads on cylindrical hohlraum wall in indirec-drive facility

In indirec-drive inertial confinement fusion facilities, aimed at the cylindrical hohlraum with two cones of laser quads and the laser quads configuration, the propagation model of laser quads in the cylindrical hohlraum was built up based on the beam smoothing schemes. On the basis, the irradiation characteristics of laser quads on vacuum cylindrical hohlraum wall were analyzed, and the laser quads arrangement was optimized preliminarily according to all the spots arrangement on hohlraum wall. Results indicate that, with the increasing of the incident angle of laser quads, the spot size of laser quads on hohlraum wall decreases, while the fractional hot spot has no significant change, and the polarization characteristics also remain almost unchanged. By further analysis of the intensity distribution and fractional hot spot of all the laser quads on hohlraum wall, it indicates that the overlap of the inner and outer cones on the hohlraum wall increases the peak intensity and raises the proportion of the hot spot in relevant area. By appropriate adjustment of the location of the focal plane and the incident angle of the inner cone laser quads, the irradiation characteristics of all the laser quads on hohlraum wall may be improved.