上海光源真空内波荡器性能的优化

The performance optimization for two in-vacuum undulators in SSRF

介绍了上海光源一期工程两台真空内波荡器的磁铁设计、磁场测量和性能优化的方法和结果.通过调整波荡器各磁极的高度来减小各磁极附近半周期磁场积分的差异,优化电子运动轨迹和辐射相位分布,使各个周期的辐射相位误差达到最小,从而增加各个周期内产生的辐射的相干性以获得高亮度的高次谐波辐射.光束线实验也测到了11次谐波辐射,并且从测到的辐射光谱推算得到的两台波荡器的均方根相位误差分别在4°和3°以内.

The magnet design and the magnetic field measurement as well as the performance optimization for two in-vacuum undulators of SSRF are introduced in this paper. By adjusting the pole heights of the undulators, the differences between the half-period field integrals are minimized and the electron trajectories and the RMS phase errors are optimized. The interferences between radiations from each period are reinforced and the intensities of the higher harmonics radiation are increased effectively. The 11th harmonics radiations are measured from the beamline experiments and the RMS phase errors obtained from the measured spectra of two undulators are less than 4° and 3° respectively.