HIAF-BRing中极化质子加速研究

Study on Acceleration of Polarized Beam at HIAF-BRing

为了更深入地研究核子性质,中国科学院近代物理研究所将在强流重离子加速器装置(HIAF)上利用极化质子束开展实验。HIAF增强器BRing能够提供最大能量9.3 Ge V/u的极化质子束,在加速过程中极化束流会遇到多次退极化共振,需要特殊设计才能使束流保持较高的极化度。利用退极化共振强度模拟程序DEPOL,研究了BRing加速过程中不同退极化共振对束流极化度的影响。结果表明,加速过程遇到的两种退极化共振将会使束流完全退极化;在BRing电子冷却段加入Full Siberian Snake可以使质子束在加速时保持较高的极化度。

In order to explore the nucleon properties in details, the polarized proton will be used for some special experiments at HIAF project in Institute of Modern Physics, Chinese Academy of Sciences（IMP,CAS）.The maximum energy of 9.3 Ge V/u for Polarized protons will be provided in the Booster Ring（BRing） at HIAF.The polarized beam experiences depolarizing resonances many times during acceleration process, so it＇s necessary to suppress those resonances to keep polarizability well by special design. In this paper, the code DEPOL is used to simulate the influence of depolarizing resonances process in BRing. According to the results, the beam＇s polarization has been destroyed completely by the depolarizing resonances in the acceleration process. And the Full Siberian Snake is chosen in the Electron Cooler part of BRing to preserve the beam＇s polarization during the acceleration, and its strength and location of the Siberian Snake are also presented here.