上海光源超导波荡器束流热负荷实验研究

Experiment study on beam heat load in superconducting undulator at the Shanghai synchrotron radiation facility

为消除在线运行时超导波荡器内束流热负荷对超导磁体的影响,并给储存环提供高真空环境,为波荡器安装了一套束流室并对其隔热效果进行研究。通过将波荡器安装至储存环内,实验对比测试了带束流与不带束流时波荡器内束流室与磁体的温度变化情况。结合G-M制冷机的工作特性,利用热平衡法测出了200 mA流强的束流对束流室和磁体产生的热负荷。实验结果显示,通束流后,束流室温度从17.2 K上升至28.3 K,磁体温度从4.3 K上升至4.4 K,束流在束流室上产生的热负荷为17.4 W,在磁体上产生的热负荷为0.2 W。表明束流室可有效屏蔽束流热负荷对磁体的影响,并使磁体工作在4.5 K以下。

In order to eliminate the influence of beam heat load to superconducting magnet in superconducting undulator and provide a high vacuum environment to the storage ring during the test for beam,a set of beam chamber was installed and its thermal insulation effect was studied.The temperature variation of the beam chamber and magnet in the undulator was measured and compared while the beam was upload and not,which was stated after the installation of undulator in the storage ring.The thermal load of 200 mA current intensity in beam chamber and magnet was tested while heat balance method was used.The results show that beam chamber temperature increases from 17.2 K to 28.3 K and magnet temperature increases from 4.3 K to 4.4 K separately.The heat load generated by beam current on the beam chamber is 17.4 W.The heat load generated by beam current on the magnet is 0.2 W.It shows that the beam chamber can effectively shield the influence of beam heat load on the magnet and make the magnet work below 4.5 K.