264 / 2023-04-23 17:27:22

Beam and target alignment at the ICF laser device using a new grid target

shooting accuracy,X-ray energy intensity,grid target

惯性约束聚变物理学 > 惯性约束聚变物理学-海报

The requirements for beam and target alignment for successful ignition experiments on the ICF laser device are stringent: the average of beams to the target must be within 30 μm. When the RMS offset between the beam center and the pre selected target center exceeds 13.6rad, there will be a bad effect on the uniformity of the radiation field, and then the experimental accuracy will be reduced too. In order to accurately evaluate the shooting accuracy of the laser device, it is necessary to test the shooting accuracy. And we can correct the offset between beam and target to meet the requirements. At present, most of the target precision testing, measuring the distribution of X-ray generated by tripling laser ablating the target instead of the location information of tripling laser reaching the target, is achieved by calculating the error between impact points and aiming points. But the fundamental and second harmonic laser will reach the target at the same time with tripling laser, and produce spurious X-ray. In this paper, we analyzed the characteristics of X-ray generated by the different beams ablating the target and studied the effects of stray light on the shooting accuracy. On this basis, a new grid target has been designed. Using this grid target we can simultaneously test the shooting accuracy of many beams. This ensures the consistency of the experiment and improves the efficiency and accuracy of the shooting accuracy test.