论文标题
RHIC的绝对氢气射流偏振仪的系统误差分析
Systematic error analysis in the absolute hydrogen gas jet polarimeter at RHIC
论文作者
论文摘要
自2004年以来，偏振原子氢气射流目标极化计（HJET）在相对论重离子对撞机（RHIC）上运行，以测量每个碰撞质子束的绝对极化。偏振仪检测器和数据采集在2015年进行了升级，以增加实心角度，能量范围并改善能量和时间分辨率。这些升级以及改进的光束强度和极化使我们能够大大减少RHIC中质子极化测量结果的统计和系统错误15（$ e_ \ text {beam} \！= \！= \！100〜 \！100〜 \！对于典型的8小时RHIC商店，测得的质子束平均极化约为$ P_ \ text {beam} \！\ sim \！55 \ pm2.0_ \ pm2.0_ \ text {stat} \ pm0.3_ \ pm0.3_ \ text {syst} \％$。弹性$ \ Mathit {pp} $分析能力，$ a_ \ text {n}（t）\！\！\ sim \！0.04 $，由大约$ |δA_\ text {n} {n}（n}（t）| \！\！\！\！0.0002 $在动量传输范围内的精度确定$ 0.001 \！<\！ - t \！<\！0.020 \，\ text {gev}^2 $。在本文中，我们介绍了HJET极化测量的详细系统误差分析。还将讨论在未来电子离子对撞机（EIC）中使用基于HJET的绝对极化器的观点。
The Polarized Atomic Hydrogen Gas Jet Target polarimeter (HJET) is operated at the Relativistic Heavy Ion Collider (RHIC) since 2004 to measure the absolute polarization of each colliding proton beam. Polarimeter detectors and data acquisition were upgraded in 2015 to increase the solid angle, energy range, and to improve the energy and time resolution. These upgrades along with an improved beam intensity and polarization allowed us to greatly reduce the statistical and systematic errors for the proton polarization measurements in RHIC Runs 15 ($E_\text{beam}\!=\!100~\text{GeV}$) and 17 ($255~\text{GeV}$). For a typical 8 hour RHIC store, the measured proton beam average polarization was about $P_\text{beam}\!\sim\!55\pm2.0_\text{stat}\pm0.3_\text{syst}\%$. The elastic $\mathit{pp}$ analyzing power, $A_\text{N}(t)\!\sim\!0.04$, was determined with a precision of about $|δA_\text{N}(t)|\!\sim\!0.0002$ in the momentum transfer squared range $0.001\!<\!-t\!<\!0.020\,\text{GeV}^2$. In this paper we present a detailed systematic error analysis of the polarization measurements at HJET. Perspectives of using the HJET based absolute polarimeters in the future Electron Ion Collider (EIC) will be also discussed.
