Paul Scherrer研究所实验R-12-01 .1的技术设计报告：用μp弹性散射研究质子“半径”之谜
Technical Design Report for the Paul Scherrer Institute Experiment R-12-01.1: Studying the Proton "Radius" Puzzle with μp Elastic Scattering
R. Gilman, E. J. Downie, G. Ron, S. Strauch, A. Afanasev, A. Akmal, J. Arrington, H. Atac, C. Ayerbe-Gayoso, F. Benmokhtar, N. Benmouna, J. Bernauer, A. Blomber… 展开作者
R. Gilman, E. J. Downie, G. Ron, S. Strauch, A. Afanasev, A. Akmal, J. Arrington, H. Atac, C. Ayerbe-Gayoso, F. Benmokhtar, N. Benmouna, J. Bernauer, A. Blomberg, W. J. Briscoe, D. Cioffi, E. Cline, D. Cohen, E. O. Cohen, C. Collicott, K. Deiters, J. Diefenbach, B. Dongwi, D. Ghosal, A. Golossanov, R. Gothe, D. Higinbotham, D. Hornidge, Y. Ilieva, N. Kalantarians, M. Kohl, B. Krusche, G. Kumbartzki, I. Lavrukhin, L. Li, J. Lichtenstadt, W. Lin, A. Liyanage, W. Lorenzon, K. E. Mesick, Z. -E. Meziani, P. Mohanmurthy, P. Moran, J. Nazeer, E. Piasetzsky, R. Ransome, R. Raymond, D. Reggiani, P. E. Reimer, A. Richter, T. Rostomyan, P. Roy, A. Sarty, Y. Shamai, N. Sparveris, N. Steinberg, I. Strakovsky, V. Sulkosky, A. S. Tadepalli, M. Taragin
The difference in proton radii measured with $μp$ atoms and with $ep$ atoms and scattering remains an unexplained puzzle. The PSI MUSE proposal is to measure $μp$ and $e p$ scattering in the same experiment at the same time. The experiment will determine cross sections, two-photon effects, form factors, and radii independently for the two reactions, and will allow $μp$ and $ep$ results to be compared with reduced systematic uncertainties. These data should provide the best test of lepton universality in a scattering experiment to date, about an order of magnitude improvement over previous tests. Measuring scattering with both particle polarities will allow a test of two-photon exchange at the sub-percent level, about a factor of four improvement on uncertainties and over an order of magnitude more data points than previous low momentum transfer determinations, and similar to the current generation of higher momentum transfer electron experiments. The experiment has the potential to demonstrate whether the $μp$ and $ep$ interactions are consistent or different, and whether any difference results from novel physics or two-photon exchange. The uncertainties are such that if the discrepancy is real it should be confirmed with $\approx$5$σ$ significance, similar to that already established between the regular and muonic hydrogen Lamb shift.
Ultracold neutron detection with 6Li-doped glass scintillators, NANOSC: a fast ultracold neutron detector for the nEDM experiment at the Paul Scherrer Institute
本文总结了旨在表征超冷中子探测的测量结果与6Li掺杂玻璃闪烁体。厚度为100-200微米的单个GS 10或GS 20中子源满足超冷中子探测要求，具有可接受的中子-伽马鉴别力。这种区分明显地通过两个澄清器的堆叠得到改善：6Li耗尽的玻璃结合到6Li富集的玻璃。光学接触粘合用于两个反射器之间，以获得完美的光学接触。闪烁体的探测效率类似于3 He Strelkov气体探测器。与数字数据采集系统耦合，计数率可达10^5计数/秒。基于这种闪烁体堆叠布置的探测器已经建成，并自2010年以来一直用于Paul Scherrer研究所的中子电偶极矩实验。给出了它对中子电偶极矩实验正常运行的响应。
The nEDM experiment at the Paul Scherrer Institute
对电子、中子或原子/分子等简单系统的非零电偶极矩（EDM）的探索是寻找超越标准模型（SM）的物理学，特别是寻找新的CP破坏源的有力途径，是对LHC实验的补充。到目前为止，没有观察到EDM信号，由RAL/Sussex/ILL合作建立的中子EDM的上限是jdnj < 3 x 10 e-26 e cm（90% C.L.）。这个极限是用一个装置设定的，该装置使用储存在室温容器中的超冷中子。瑞士Paul Scherrer研究所的nEDM合作旨在很快达到10 e-27 e cm范围的灵敏度。我将介绍实验的现状，并讨论未来的前景。
Dynamic stabilization of the magnetic field surrounding the neutron electric dipole moment spectrometer at the Paul Scherrer Institute
在这项工作中所描述的周围场补偿（SFC）系统安装在周围的四层金属磁屏蔽的中子电偶极矩谱仪位于保罗谢勒研究所。SFC系统将外部磁场的DC分量减小约20倍。在约2.5 m x 2.5 m x 3 m的控制体积内，磁场的干扰在$10^{-3}$ Hz至0.5 Hz的带宽下衰减5至50倍，这对应于长于数百秒的积分时间，代表了nEDM测量的重要时间尺度。这些屏蔽因子适用于来自任意源的随机环境噪声。这是通过比例积分反馈稳定系统来实现的，该比例积分反馈稳定系统包括比例因子的正则化伪逆矩阵，该比例因子将所有传感器位置处的磁场变化与SFC线圈中的电流变化相关联。
The George Washington University（乔治华盛顿大学）；Argonne National Laboratory（阿贡国家实验室）；PSI Center for Neutron and Muon Sciences（瑞士保罗谢尔研究所中子与缪子科学中心）；New Mexico State University（新墨西哥州立大学）；Temple University（天普大学）；Stony Brook University（石溪大学）；Hampton University（汉普顿大学）；Massachusetts Institute of Technology（麻省理工学院）；Rutgers, The State University of New Jersey（罗格斯大学）
MUSE实验通过同时进行电子-质子和缪子-质子散射来解决质子半径谜题，本文介绍了用于消除触发层背景的Target Chamber Post Veto（TCPV）探测器的设计和性能。
