NSF-BSF: Exploring the Proton Radius Puzzle and Phenomena Beyond the Standard Model with Low-energy Lepton Scattering

NSF-BSF：利用低能轻子散射探索质子半径之谜和超越标准模型的现象

• 批准号: 1812402
• 负责人: Michael Kohl
• 金额: $ 69.6万
• 依托单位: Hampton University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2023-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1812402&HistoricalAwards=false
• 关键词: NSF; BSF; Exploring; Proton; Radius

This award provides funding for Dr. Michael Kohl and his group at Hampton University, a Historically Black College und University in Virginia, USA. The group has a core function in the Muon Scattering Experiment (MUSE) in preparation at Paul-Scherrer Institute in Switzerland, and in the DarkLight project at the Thomas Jefferson National Accelerator Facility (Jefferson Laboratory) in the US. The MUSE project is a dedicated investigation of the so-called proton radius puzzle, a very prominent topic in nuclear physics. The experiment will measure the proton charge radius with high precision via lepton-proton elastic scattering, and will compare the interactions of muons and electrons of either charge with the proton at a fundamental level. The experiment will severely constrain possible explanations of the puzzle and has the potential to reveal new physics beyond the Standard Model. The DarkLight experiment in preparation at Jefferson Lab aims to discover a new particle associated with a fifth interaction suited to explain several observed anomalies in particle physics while offering a connection to dark matter. Both projects offer high-profile opportunities for students and postdocs at the forefront of international nuclear and particle physics research. The PI's research program has many facets and offers excellent opportunities for cutting-edge education and research purpose domestically and abroad. This proposal combines state-of-the-art detector development at Hampton University with its application in forefront research at PSI and at Jefferson Lab. This provides new research and educational opportunities at first-class research facilities for students from minority populations, predominantly African-Americans, and postdoctoral researchers. The development and operation of GEM detectors in the MUSE and DarkLight environments will be beneficial to advance this still novel technology with potential future applications in other experiments, as well as in the medical sector. The MUSE experiment has been proposed and approved to provide key insight in the quest to explain the so-called proton radius puzzle - the over five-standard deviation discrepancy between proton charge radius measurements with electronic and muonic probes, respectively. Possible explanations also include new physics beyond the Standard Model. The MUSE experiment aims to address one of the most pressing questions in nuclear and particle science to date. MUSE uses mixed muon and electron beams of either charge (mu+, e+, mu-, e-) to make precise measurements of the lepton-proton elastic scattering cross sections and proton form factors, with the goal to extract the proton charge radius for each probe. It will determine with the highest precision, model independently and conclusively, if there is any proton charge radius difference observed in electron versus muon scattering. At the same time it will determine the role of two-photon exchange and provide tight constraints on theory. Dr. Kohl is one of the co-initiators of the MUSE project. The role of Dr. Kohl's group in MUSE is essential to this project. This project focuses on the challenging task of high-resolution beam particle tracking at MUSE with GEM detectors, in a way not done before at low beam energies. The tracker is exposed to high rate density and beam flux, and needs to operate efficiently at a trigger rate of a few kHz. The DarkLight Phase-I project at Jefferson Lab includes a focused search for a dark photon or neutral boson in the mass region around 17 MeV/c2, where evidence for a fifth-force carrier has been reported.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

该奖项为迈克尔·科尔（Michael Kohl）博士及其小组汉普顿大学（Hampton University）提供了资金，这是美国弗吉尼亚州历史上历史悠久的黑人学院UND大学。该小组在瑞士的Paul-Scherrer Institute准备MUON散射实验（MUSE）以及美国托马斯·杰斐逊国家加速器设施（杰斐逊实验室）的Darklight项目中具有核心功能。缪斯项目是对所谓的质子半径难题的专门研究，这是核物理学中非常重要的话题。该实验将通过Lepton-Proton弹性散射高精度测量质子电荷半径，并将比较任何一种电荷的MUON和电子与质子在基本水平上的相互作用。该实验将严重限制难题的可能解释，并有可能揭示超出标准模型的新物理。在杰斐逊实验室准备的黑暗灯实验旨在发现与适合解释粒子物理中观察到的几个异常相关的第五相互作用相关的新粒子，同时提供与暗物质的连接。这两个项目都为学生和博士后在国际核和粒子物理研究的最前沿都提供了备受瞩目的机会。 PI的研究计划有许多方面，并为国内外提供了极大的教育和研究目的。该提案将汉普顿大学的最先进的探测器开发与PSI和杰斐逊实验室的最前沿研究的应用相结合。这为少数民族，主要是非裔美国人和博士后研究人员的学生提供了一流研究机构的新研究和教育机会。缪斯和黑暗环境中宝石探测器的开发和操作将有益于在其他实验以及医疗领域的未来应用中推进这种新颖的技术。缪斯实验已被提出并批准，以提供关键的见解，以寻求解释所谓的质子半径拼图 - 分别用电子和muonic探针测量质子电荷半径之间的五个标准偏差差异。可能的解释还包括标准模型之外的新物理。缪斯实验旨在解决迄今为止核和粒子科学中最紧迫的问题之一。缪斯使用混合的muon和电子束（Mu+，E+，Mu-，e-）来精确测量Lepton-Proton弹性弹性散射横截面和质子形式，以便为每个探针提取质子电荷半径。它将以最高的精度独立和结论地确定，如果在电子散射与muon散射中观察到任何质子电荷半径差。同时，它将确定两光子交换的作用，并在理论上提供严格的约束。 Kohl博士是Muse项目的共同企业之一。 Kohl博士在Muse中的作用对于这个项目至关重要。该项目着重于用宝石探测器在Muse进行高分辨率梁粒子跟踪的具有挑战性的任务，在低光束能量之前没有做过。跟踪器暴露于高速率密度和梁通量，并且需要以几个kHz的触发速率有效运行。杰斐逊实验室（Jefferson Lab）的Darklight I Paship-I项目包括对大众区域的深色光子或中性玻色子进行重点搜索，据报道，在17 MEV/C2左右，已有报道的第五强承运人的证据。这项奖项反映了NSF的法定任务，并被认为是通过该基金会的知识分子优点和广泛的影响来审查CRETIRIA的法定任务。

项目成果

Ruling out Color Transparency in Quasielastic C12(e,e′p) up to Q2 of 14.2 (GeV/c)2

排除准弹性 C12(e,e−p) 中 Q2 的颜色透明度达到 14.2−−(GeV/c)2

• DOI: 10.1103/physrevlett.126.082301
• 发表时间: 2021
• 期刊: Physical Review Letters
• 影响因子: 8.6
• 作者: Bhetuwal, D.;Matter, J.;Szumila-Vance, H.;Kabir, M. L.;Dutta, D.;Ent, R.;Abrams, D.;Ahmed, Z.;Aljawrneh, B.;Alsalmi, S.
• 通讯作者: Alsalmi, S.

Instrumental uncertainties in radiative corrections for the MUSE experiment

MUSE 实验辐射校正中的仪器不确定性

• DOI: 10.1140/epja/s10050-023-01215-0
• 发表时间: 2024
• 期刊: The European Physical Journal A
• 作者: Li, L.;Strauch, S.;Bernauer, J. C.;Briscoe, W. J.;Christopher Ndukwe, A.;Cline, E.;Cohen, D.;Deiters, K.;Downie, E. J.;Fernando, I. P.
• 通讯作者: Fernando, I. P.

Measurement of structure dependent radiative K+ → e+νγ decays using stopped positive kaons

使用停止的正 kaons 测量结构依赖的辐射 K α γ 衰变

• DOI: 10.1016/j.physletb.2022.136913
• 发表时间: 2022
• 期刊: Physics Letters B
• 影响因子: 4.4
• 作者: Ito, H.;Kobayashi, A.;Bianchin, S.;Cao, T.;Djalali, C.;Dongwi, D.H.;Gautam, T.;Gill, D.;Hasinoff, M.D.;Horie, K.
• 通讯作者: Horie, K.

Performance check of the CsI(Tl) calorimeter for the J-PARC E36 experiment by observing e+ from muon decay

通过观察 μ 子衰变中的 e 来检查 J-PARC E36 实验中 CsI(Tl) 量热仪的性能

• DOI: 10.1016/j.nima.2018.05.065
• 发表时间: 2018
• 期刊: Detectors and Associated Equipment
• 作者: Ito, H.;Horie, K.;Shimizu, S.;Bianchin, S.;Djalali, C.;Dongwi, B.;Gill, D.;Hasinoff, M.D.;Igarashi, Y.;Imazato, J.
• 通讯作者: Imazato, J.

Design and operation of a windowless gas target internal to a solenoidal magnet for use with a megawatt electron beam

• DOI: 10.1016/j.nima.2019.05.071
• 发表时间: 2019-03
• 期刊: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
• 作者: S. Lee;R. Corliss;I. Friščić;R. Alarcon;S. Aulenbacher;J. Balewski;S. Benson;J. Bernauer;J. Bessuille;J. Boyce;J. Coleman;D. Douglas;C. Epstein;P. Fisher;S. Frierson;M. Garçon;J. Grames;D. Hasell;C. Hernández-García;E. Ihloff;R. Johnston;K. Jordan;R. Kazimi;J. Kelsey;M. Kohl;A. Liyanage;M. McCaughan;R. Milner;P. Moran;J. Nazeer;D. Palumbo;M. Poelker;G. Randall;S. Steadman;C. Tennant;C. Tschalär;C. Vidal;C. Vogel;Yayu Wang;S. Zhang