快校正磁铁电源是光源和加速器中重要的设备。随着光源性能的提升，加速器对快校正磁铁电源的性能也提出了更高要求。为满足快校正磁铁电源性能要求和简化设计过程，开展了快校正磁铁电源控制策略和仿真研究，并提出了PI控制加二阶相位补偿的方法作为快校正磁铁电源的控制策略；利用伯德图设计快校正磁铁电源的相位补偿参数，以提高电源系统相位裕量。该方法不仅保证了电源系统工作在深度负反馈状态，而且简化了相位补偿的参数计算过程。为了验证控制策略的正确性和有效性，提出用压控电压源代替开关器件开展电源性能仿真的方法。仿真结果验证了上述控制策略的可行性和有效性，同时验证了上述仿真方法的有效性和高效性。

Fast neutron absorption spectroscopy is widely used in the study of nuclear structure and element analysis. However, due to the traditional neutron source pulse duration being of the order of nanoseconds, it is difficult to obtain a high-resolution absorption spectrum. Thus, we present a method of ultrahigh energy-resolution absorption spectroscopy via a high repetition rate, picosecond duration pulsed neutron source driven by a terawatt laser. The technology of single neutron count is used, which results in easily distinguishing the width of approximately 20 keV at 2 MeV and an asymmetric shape of the neutron absorption peak. The absorption spectroscopy based on a laser neutron source has one order of magnitude higher energy-resolution power than the state-of-the-art traditional neutron sources, which could be of benefit for precisely measuring nuclear structure data.

负离子源中性束注入（NNBI）系统是聚变堆主机关键系统综合研究设施（CRAFT）的组成部分，其目标是开展NNBI相关的科学与工程问题研究，为未来聚变堆NNBI系统的研制与运行积累经验。加速器的束流光学特性决定着最终形成束流的发散性，进而影响着束流在加速器和束线中的传输效率，这对NNBI系统的高功率、高能量、长脉冲运行至关重要。为此，采用IBSimu离子束流模拟程序对目前CRAFT NNBI的400 keV加速器电极系统的物理设计进行束流光学特性分析与评估。目前该套电极结构的设计与ITER负离子源类似，束发散的计算结果满足设计要求。在负离子束流密度较高时（100～300 A/m²范围内），具有更小束发散角；引出距离（5～7 mm范围内）和加速距离（88～110 mm范围内）的适当增加，也呈现出束发散角下降趋势。

Exploiting high-energy electron beams colliding into high-intensity laser pulses brings an opportunity to reach high values of the dimensionless rest-frame acceleration $\chi$ and thereby invoke processes described by strong-field quantum electrodynamics (SFQED). Measuring deviations from the results of Furry-picture perturbation theory in SFQED at high $\chi$ can be valuable for testing existing predictions, as well as for guiding further theoretical developments. Nevertheless, such experimental measurements are challenging due to the probabilistic nature of the interaction processes, dominating signals of low- $\chi$ interactions and limited capabilities to control and measure the alignment and synchronization in such collision experiments. Here we elaborate a methodology of using approximate Bayesian computations for drawing statistical inferences based on the results of many repeated experiments despite partially unknown collision parameters that vary between experiments. As a proof-of-principle, we consider the problem of inferring the effective mass change due to coupling with the strong-field environment.

北京串列加速器核物理国家实验室HI-13串列加速器（以下简称串列加速器）投入运行已有35周年的时间了。为了保持这台加速器的性能，运维团队以保障加速器的运行能力为中心，分别从攻克加速器关键部件研制、培养好运维人员队伍以及提高机时利用效率等几个方面开展了工作。其中，重点阐述了关键部件研制及子系统的升级改造。通过这些工作的开展，保持并提升了这台加速器的性能，加速器也处于良好的安全稳定运行状态。最后，指出了串列加速器所面临的问题及未来的发展规划。