摘要
针对甚多束激光辐照下的直接驱动靶面光强均匀分布开展了系统研究.利用球谐模分析选定了可实现均匀辐照的靶面弹着点极角分布,并通过数值模拟确定了以等效48束激光直接驱动辐照下靶面三环弹着点极角位置分别为22.4?,47.7?和73.6?.基于特定装置构型分析了实现极向直接驱动时对各路激光指向的修正,并对光束截面焦斑进行了优化,实现了极向直接驱动下的靶面均匀辐照.
Capsule illumination uniformity obtained by direct driving lasers from several tens of directions is studied system-atically. The best polar angles of the three focal spot rings on the capsule are determined to be 22.4°, 47.7°, and 73.6°by a spherical-harmonic mode analysis and a numerical simulation. Based on the configuration of indirect laser driven facility, we have optimized the beam re-directions and the focal spot distributions for polar direct drive, which smooth successfully the illumination distribution on the capsule.Laser driven inertial confinement fusion is an important way to achieve controllable nuclear fusion for human be-ings, which includes two laser-driven schemes—directly driving and indirectly driving scheme. Since the indirect driving scheme considerably relaxes the strict requirements for laser performance and decreases the engineering difficulties, the main laser facilities around the world have adopted the indirect driving scheme, such as the National Ignition Facility in the U. S., the Laser Megajoule in France, and the SG series laser drivers in China.Meanwhile, scientists keep developing the key technologies for directly driving and have made great progress. For example, the fast ignition and shock ignition are two new methods to achieve fusion ignition in the direct driving scheme, which attracted lots of attention in the past few years. However, the main laser drivers for inertial confinement fusion research are configured as indirect drivers, which are not suitable for direct driving experiments. So a compromising suggestion was proposed that by redirecting the lasers, changing the laser energy distributions, designing new type of targets, and so on, a radiation field which is very close to a direct driving radiation field can be simulated in a laser facility that is configured as an indirect driver. This is the so called polar direct drive method that provides a feasible way for primary researches on direct driving technologies in an indirect laser driver. Such experiments ha
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2015年第19期218-224,共7页
Acta Physica Sinica
基金
国家高技术研究发展计划资助的课题~~
关键词
靶面辐照均匀性
极向直接驱动
惯性约束聚变
capsule illumination uniformity
polar direct drive
SG-III laser facility
