利用新研制的聚变反应速率测量系统, 在神光Ⅲ原型装置上测量了间接驱动时充DT气体的玻璃球壳内爆靶丸的聚变反应速率的时间历程, 获得了DT中子产额约为1010时的聚变反应速率随时间的变化过程, 发现了聚变中子发射在时间上的双峰结构。利用辐射流体程序对聚变中子在时间上的双峰结构进行了数值模拟, 发现双峰结构分别由冲击压缩过程和惯性压缩过程产生, 靶丸壳层厚度不同时产生的聚变中子发射双峰强度比变化可能是由靶丸的初始表面调制度不同所致。通过理论模拟与实验结果的对比, 验证了中子聚变反应历程的双峰结构。

The relationship of the roughness degree of ablation shell and the two peaks of fusion reaction rate was analyzed. We developed a system for fusion reaction history measurement with high temporal resolution, and applied this system to the SG-Ⅲ prototype for measuring fusion reaction rate. Fusion reaction rate history was measured for the first time with deuterium-tritium filled targets under neutron yields of about 1010. We anatomized possible influence factors during fusion reaction rate’s measuring. The two peaks of reaction rate can be obtained from the simulation results, and have been confirmed with the experimental results. It is found that neutrons in our experiment are generated by the first peak which is called the shock peak. The simulation and experimental results can provide strong technical support for the research on fusion reaction rate in inertial confinement fusion.