Tsuchiya K, Shioya T
Accelerator Laboratory, High Energy Accelerator Research Organization (KEK), Tsukuba 1-1 Oho, Japan.
Rev Sci Instrum. 2015 Apr;86(4):043305. doi: 10.1063/1.4918793.
We have developed a practical method for determining an excellent initial arrangement of magnetic arrays for a pure-magnet Halbach-type undulator. In this method, the longitudinal magnetic field distribution of each magnet is measured using a moving Hall probe system along the beam axis with a high positional resolution. The initial arrangement of magnetic arrays is optimized and selected by analyzing the superposition of all distribution data in order to achieve adequate spectral quality for the undulator. We applied this method to two elliptically polarizing undulators (EPUs), called U#16-2 and U#02-2, at the Photon Factory storage ring (PF ring) in the High Energy Accelerator Research Organization (KEK). The measured field distribution of the undulator was demonstrated to be excellent for the initial arrangement of the magnet array, and this method saved a great deal of effort in adjusting the magnetic fields of EPUs.
我们已经开发出一种实用方法，用于确定纯磁哈尔巴赫型波荡器磁阵列的优良初始排列。在该方法中，使用移动霍尔探头系统沿着束流轴以高位置分辨率测量每个磁体的纵向磁场分布。通过分析所有分布数据的叠加来优化和选择磁阵列的初始排列，以便为波荡器实现足够的光谱质量。我们将此方法应用于高能加速器研究机构（KEK）光子工厂储存环（PF环）中的两个椭圆极化波荡器（EPU），分别称为U#16 - 2和U#02 - 2。结果表明，所测量的波荡器磁场分布对于磁体阵列的初始排列非常理想，并且该方法在调整EPU磁场方面节省了大量精力。
