RUI: Nucleon Structure Studies via Electron Scattering at JLab 12 GeV

RUI：在 JLab 12 GeV 上通过电子散射进行核子结构研究

• 批准号: 1812369
• 负责人: Peter Monaghan
• 金额: $ 24.28万
• 依托单位: Christopher Newport 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 2022-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1812369&HistoricalAwards=false
• 关键词: RUI; Nucleon; Structure; Studies; via

It has been established that protons and neutrons (nucleons) have a substructure made up of elementary constituent particles called quarks and gluons. Quantum Chromodynamics (QCD) is an established theory of how these constituents interact giving rise to the strong nuclear force and the fundamental properties of nucleons. The research program supported by this grant is aimed at improving the fundamental understanding of nucleon structure. This goal will be achieved through electron scattering experiments to be performed at the Thomas Jefferson National Accelerator Facility (JLab). These experiments will measure the spatial distributions of electric charge and current in both the proton and the neutron; this information is encoded in the nucleon electromagnetic form factors. A fundamental understanding of the nucleon form factors in terms of QCD is one of the outstanding challenges in nuclear physics today. Why and how do quarks forms colorless hadrons with only two stable configurations, the proton and neutron? One important step towards addressing this challenge is to characterize the internal structure of the nucleon via form factor measurements. The anticipated research activities will cover a range of both hardware and software projects. These projects will provide outstanding research opportunities for undergraduate students, furthering their education outside the classroom, preparing them for a career in science, technology, engineering and mathematics (STEM) and laying the foundations for successful graduate studies.The funding support for this research program will enable the PI and Christopher Newport University students to contribute to a number of projects at JLab, aimed at improving the fundamental understanding of nucleon structure. The proposed projects include an experimental effort - the Super Bigbite Spectrometer program (SBS) - and a phenomenology effort - CTEQ-JLab (CJ) - both of which address fundamental questions of hadronic structure in the QCD framework. The SBS program comprises high impact experiments studying the electromagnetic form factors of both the proton and neutron at a much higher momentum transfer than previously studied. The new data from the SBS experiments will allow a partonic flavor decomposition of the form factors to be performed, which in turn can be tested using calculations provided by the CJ effort. The PI is leading the commissioning effort of one of the SBS detector systems, as well as contributing to the analysis effort in the CJ projectThis 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.

已经确定质子和中子（核子）具有由称为夸克和胶子的基本组成粒子组成的子结构。量子色动力学 (QCD) 是关于这些成分如何相互作用从而产生强核力和核子基本性质的既定理论。这笔赠款支持的研究计划旨在提高对核子结构的基本了解。这一目标将通过在托马斯·杰斐逊国家加速器设施（JLab）进行的电子散射实验来实现。这些实验将测量质子和中子中电荷和电流的空间分布；该信息被编码在核子电磁形状因子中。从 QCD 角度对核子形状因素的基本理解是当今核物理学面临的突出挑战之一。夸克为什么以及如何形成只有质子和中子两种稳定构型的无色强子？解决这一挑战的一个重要步骤是通过形状因子测量来表征核子的内部结构。预期的研究活动将涵盖一系列硬件和软件项目。这些项目将为本科生提供出色的研究机会，在课堂外继续深造，为他们在科学、技术、工程和数学 (STEM) 领域的职业生涯做好准备，并为成功的研究生学习奠定基础。该研究项目的资金支持将使 PI 和克里斯托弗纽波特大学的学生能够为 JLab 的多个项目做出贡献，旨在提高对核子结构的基本理解。拟议的项目包括一项实验工作 - Super Bigbite 光谱仪计划 (SBS) - 和一项现象学工作 - CTEQ-JLab (CJ) - 两者都解决了 QCD 框架中强子结构的基本问题。 SBS 项目包括高影响实验，研究质子和中子的电磁形状因数，其动量传递比之前研究的要高得多。 SBS 实验的新数据将允许对形状因素进行部分风味分解，进而可以使用 CJ 工作提供的计算进行测试。 PI 正在领导其中一个 SBS 探测器系统的调试工作，并为 CJ 项目的分析工作做出贡献。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力优点和更广泛的影响审查进行评估，被认为值得支持标准。

项目成果

High-resolution hypernuclear spectroscopy at Jefferson Lab, Hall A

杰斐逊实验室 A 厅的高分辨率超核光谱

• DOI: 10.1103/physrevc.99.054309
• 发表时间: 2019
• 期刊: Physical Review C
• 影响因子: 3.1
• 作者: Garibaldi, F.;Acha, A.;Ambrozewicz, P.;Aniol, K. A.;Baturin, P.;Benaoum, H.;Benesch, J.;Bertin, P. Y.;Blomqvist, K. I.;Boeglin, W. U.
• 通讯作者: Boeglin, W. U.

Measurement of the generalized spin polarizabilities of the neutron in the low-Q2 region

低 Q2 区域中子广义自旋极化率的测量

• DOI: 10.1038/s41567-021-01245-9
• 发表时间: 2021
• 期刊: Nature Physics
• 影响因子: 19.6
• 作者: Sulkosky, Vincent;Peng, Chao;Chen, Jian-ping;Deur, Alexandre;Abrahamyan, Sergey;Aniol, Konrad A.;Armstrong, David S.;Averett, Todd;Bailey, Stephen J.;Beck, Arie
• 通讯作者: Beck, Arie

Proton form factor ratio \mu_p G_E^p/G_M^p from double spin asymmetry

来自双自旋不对称的质子形状因子比率 mu_p G_E^p/G_M^p

• 发表时间: 2020
• 期刊: Physical review
• 作者: Liyanage, A.;Armstrong, W.;Kang, H.;Maxwell, J.;Mulholland, J.;Ndukum, L.;Ahmidouch, A.;Albayrak, I.;Asaturyan, A.;Ates, O.
• 通讯作者: Ates, O.

Measurement of double-polarization asymmetries in the quasi-elastic He→3(e→,e′p) process

准弹性 He−3(e−,e−p) 过程中双极化不对称性的测量

• DOI: 10.1016/j.physletb.2018.10.063
• 发表时间: 2019
• 期刊: Physics Letters B
• 影响因子: 4.4
• 作者: Mihovilovič, M.;Jin, G.;Long, E.;Zhang, Y.-W.;Allada, K.;Anderson, B.;Annand, J.R.M.;Averett, T.;Bertozzi, W.;Boeglin, W.
• 通讯作者: Boeglin, W.

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.