Studies of the Structure of Light Mesons and Nucleons through Exclusive Reactions

通过排他反应研究轻介子和核子的结构

• 批准号: 1714133
• 负责人: Tanja Horn
• 金额: $ 44.8万
• 依托单位: Catholic University of America
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-08-01 至 2021-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1714133&HistoricalAwards=false
• 关键词: Studies; Structure; Light; Mesons; Nucleons

Pions and kaons are the lightest subatomic particles and play a unique role in nature; our understanding of them is essential for explaining the fundamental structure of matter. This research is centered on precision measurements of pion and kaon properties that have the potential to reveal the three-dimensional structure of the nucleons, the protons and neutrons that, together with their interactions, generate nearly of the mass of the visible universe. As such, this work probes the fundamental structure of that part of the universe that we can see. This project is part of a series of experiments taking place at the Thomas Jefferson National Accelerator Laboratory. Early career scientists, graduate students, and undergraduate students play an integral part in this project, which provides them with opportunities to further develop their training and education. These include gaining experience in the design, assembly, and testing of modern instrumentation for the detection of radiation and subatomic particles and fast signal processing electronics, and in analyzing scientific data. Furthermore, learning to work in a large international scientific community will prepare early career scientists and students for the modern work environment at academic institutions, national laboratories, and industry. This program is focused on precision measurements of pion and kaon form factors and structure functions, and validation of our understanding of hard exclusive and semi-inclusive reactions towards 3D hadron imaging and potential future flavor decomposition. Form factors are the most basic quantity towards understanding transverse spatial structure. The structure functions are expected to be different for pions, kaons, and nucleons regarding sea quarks and gluons and provide basic information about the origin of mass. 3D hadron imaging allows for the extraction of correlations between quark longitudinal momentum and transverse position from the experiment using factorization theorems. To validate the meson factorization theorems and potential future flavor decomposition, one has to measure the longitudinal and transverse (L/T) separated cross sections. This project plays a central role in this effort through precision pion, and kaon L/T separated cross section measurements at the 12 GeV Jefferson Lab and development of measurements of the, to date, mostly unknown pion and kaon structure functions at a potential future Electron-Ion Collider.

介子和介子是最轻的亚原子粒子，在自然界中发挥着独特的作用；我们对它们的理解对于解释物质的基本结构是必不可少的。这项研究的中心是对pion和kaon性质的精确测量，这些性质有可能揭示核子的三维结构，即质子和中子，它们与它们的相互作用产生了几乎可见宇宙的质量。因此，这项工作探索了我们可以看到的那部分宇宙的基本结构。该项目是托马斯·杰斐逊国家加速器实验室进行的一系列实验的一部分。早期职业科学家、研究生和本科生在这个项目中发挥着不可或缺的作用，这为他们提供了进一步发展自己的培训和教育的机会。其中包括在设计、组装和测试用于检测辐射和亚原子粒子的现代仪器和快速信号处理电子设备以及分析科学数据方面积累经验。此外，学习在大型国际科学界工作将使早期职业科学家和学生为学术机构、国家实验室和工业的现代工作环境做好准备。这项计划专注于对介子和介子形状因子和结构函数的精确测量，以及验证我们对3D强子成像和潜在未来风味分解的硬排斥和半包容反应的理解。形状因子是理解横向空间结构的最基本的量。关于海夸克和胶子，介子、介子和核子的结构函数应该是不同的，并提供了关于质量起源的基本信息。三维强子成像允许使用因式分解定理从实验中提取夸克纵向动量和横向位置之间的关联。为了验证介子因式分解定理和潜在的未来味道分解，我们必须测量纵向和横向(L/T)分离的截面。该项目在这项工作中发挥了核心作用，在12GeV的杰斐逊实验室进行了精确的介子和介子L/T分离的截面测量，并在一个潜在的未来电子-离子对撞机上开发了迄今为止大多未知的介子和介子结构函数的测量结果。

项目成果

Exclusive π+ electroproduction off the proton from low to high −t

独家 Ï 质子电生产从低到高 Ït

• DOI: 10.1103/physrevc.100.065204
• 发表时间: 2019
• 期刊: Physical Review C
• 影响因子: 3.1
• 作者: Basnet, S.;Huber, G. M.;Li, W. B.;Blok, H. P.;Gaskell, D.;Horn, T.;Aniol, K.;Arrington, J.;Beise, E. J.;Boeglin, W.
• 通讯作者: Boeglin, W.

Pion and kaon structure functions at an electron-ion collider

电子离子对撞机中的π介子和介子结构函数

• DOI: 10.1063/1.5040208
• 发表时间: 2018
• 期刊: AIP Conference Proceedings
• 作者: Horn, Tanja

Measurements of Nonsinglet Moments of the Nucleon Structure Functions and Comparison to Predictions from Lattice QCD for Q2=4 GeV2

核子结构函数非单矩的测量以及与 Q2=4–GeV2 晶格 QCD 预测的比较

• DOI: 10.1103/physrevlett.123.022501
• 发表时间: 2019
• 期刊: Physical Review Letters
• 影响因子: 8.6
• 作者: Albayrak, I.;Mamyan, V.;Christy, M. E.;Ahmidouch, A.;Arrington, J.;Asaturyan, A.;Bodek, A.;Bosted, P.;Bradford, R.;Brash, E.
• 通讯作者: Brash, E.

Deeply virtual Compton scattering off the neutron

• DOI: 10.1038/s41567-019-0774-3
• 发表时间: 2020-01
• 期刊: Nature Physics
• 影响因子: 19.6
• 作者: M. Benali;C. Desnault;Malek Mazouz;Z. Ahmed;H. Albataineh;K. Allada;K. Aniol;V. Bellini;W. Boeglin

Scintillating crystals for the Neutral Particle Spectrometer in Hall C at JLab

JLab C 厅中性粒子光谱仪的闪烁晶体

• DOI: 10.1016/j.nima.2019.163375
• 发表时间: 2020
• 期刊: Detectors and Associated Equipment
• 作者: Horn, T.;Berdnikov, V.V.;Ali, S.;Asaturyan, A.;Carmignotto, M.;Crafts, J.;Demarque, A.;Ent, R.;Hull, G.;Ko, H.-S.
• 通讯作者: Ko, H.-S.