Absolute polarization measurement of the 200 MeV proton beam at BNL Linac.
Absolute polarization measurement of the 200 MeV proton beam at BNL Linac.
复制标题
BNL 直线加速器上 200 MeV 质子束的绝对偏振测量。
DOI：
10.22323/1.324.0024
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
A. Zelenski
中科院分区：
文献类型：
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作者：
A. Poblaguev;G. Atoian;A. Zelenski
为了对BNL直线加速器上垂直极化的200 MeV质子束进行绝对校准，我们在左右对称闪烁探测器上探测了束流在碳靶上散射产生的弹性质子。探测器位于角度$\theta_\text{Lab}=\pm16.2 ^\circ $，弹性散射的分析功率具有99.35\%的局部最大值。在旋光计的两个臂中安装了厚度为40 mm的可变长度的铜吸收体，以抑制非弹性质子。在RHIC运行2017期间，我们升级了具有250 MHz 12位WFD的旋光仪DAQ。所有检测到的事件的详细分析，使我们能够适当地隔离散射质子信号，并控制在原位的非弹性质子抑制的效率。绝对偏振测量的系统误差为$sigma P^syst/Psim 0. 5 $。
For absolute calibration of the vertically polarized \unit{200}{\MeV} proton beam at BNL Linac, we detect in left/right symmetric scintillator detectors the elastic protons from the beam scattering on the Carbon target. The detectors are located at angles $\theta_\text{Lab}=\pm16.2^\circ$, at which analyzing power of the elastic scattering has local maximum of 99.35\%. Variable length copper absorbers of $\sim$\unit{40}{\mm} thickness are installed in both arms of the polarimeter to suppress the inelastic protons. During RHIC Run 2017 we upgraded the polarimeter DAQ with a \unit{250}{\MHz}12 bit WFD. The detailed analysis of all detected events allowed us to properly isolate scattered proton signals and to control in-situ the efficiency of inelastic proton suppression. The systematic error in absolute polarization measurement was confirmed to be $\sigma_P^\text{syst}/P\sim0.5\%$.