论文标题
在射频四极中形成的纵相空间的高维度表征
High dimensional characterization of the longitudinal phase space formed in a radio frequency quadrupole
论文作者
论文摘要
现代加速器前端几乎完全包括射频四足动物，用于初始捕获和聚焦低能光束。 RFQ中的动力学定义纵向束参数。用Parmteq播种的SNS RFQ模拟具有逼真的LEBT分布，产生了2.5 MeV，40 mA H-梁，均方根发射130 deg-kev。在测量中，对纵向相空间进行了详细的表征，包括对纵向发射对横向坐标的依赖性的新研究。这项工作引入了一种新的虚拟缝隙技术，该技术在能量光谱仪中提供了子缝隙分辨率以及可视化4D相空间数据的方法。通过仿真和测量，确认RFQ形成的束具有显着的内部相关结构。高维特征被证明是定性协议。但是，测得的RMS发射率比预测的最高30％，更接近95摄氏度的设计值。
Modern accelerator front ends almost exclusively include radio-frequency quadrupoles for initial capture and focusing of the low-energy beam. Dynamics in the RFQ define the longitudinal bunch parameters. Simulation of the SNS RFQ with PARMTEQ seeded with a realistic LEBT distribution produces a 2.5 MeV, 40 mA H- beam with root-mean-square emittance of 130 deg-keV. In measurement, a detailed characterization of the longitudinal phase space is made, including a novel study of the dependence of longitudinal emittance on transverse coordinates. This work introduces a new virtual slit technique that provides sub-slit resolution in an energy spectrometer as well as an approach for visualizing 4D phase space data. Through simulation and measurement, the RFQ-formed bunch is confirmed to have significant internal correlated structure. The high-dimensional features are shown to be in qualitative agreement. However, the measured rms emittances are up to 30% lower than predicted, closer to the design value of 95 deg-keV.
