RUI: Studies of Nucleon Structure at Jefferson Lab

RUI：杰斐逊实验室的核子结构研究

• 批准号: 2014114
• 负责人: Edward Brash
• 金额: $ 51万
• 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: 2020
• 资助国家: 美国
• 起止时间: 2020-08-15 至 2024-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2014114&HistoricalAwards=false
• 关键词: RUI; Studies; Nucleon; Structure; Jefferson

It is now a well-established fact that nucleons (protons and neutrons) are made up of more elementary constituents: quarks and gluons. The research program supported by this award aims to study the internal structure of nucleons. More specifically, the PIs and their team of students will scatter electrons from protons and neutrons at Jefferson Laboratory to measure the electric and magnetic properties of the nucleon, which represent where the quarks and gluons are inside the nucleons. This group contributes to these efforts through the design of new experiments, the construction of advanced particle detectors, and the development of novel analysis, modeling, and data acquisition software. The PIs provide meaningful, substantive projects to both undergraduate and graduate students. The PIs’ mentoring of the students in these challenging projects prepares the students for STEM careers.This group’s long-established program of experiments embody Jefferson Lab’s fundamental mission: to elucidate the underlying structure of protons, neutrons, and mesons. They focus on experiments that will further our understanding of the quark spin structure of the proton and neutron in the non-perturbative regime. As this program moves forward using Jefferson Lab’s recently commissioned 12 GeV electron beam, this group is poised to take advantage of the increased physics reach. The PIs continue to lead efforts to extend the measurements of the proton and neutron electromagnetic form factors to the highest momentum transfers possible at Jefferson Lab, and also investigate possible modification of the proton form factor ratio within the nuclear medium. These experiments provide strong tests of the available theoretical models of nucleon structure, and at the same time serve as an impetus for the development of new and more advanced models based on Quantum Chromo-Dynamics (QCD).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.

现在公认的事实是，核子(质子和中子)是由更基本的成分组成的：夸克和胶子。该奖项支持的研究项目旨在研究核子的内部结构。更具体地说，PI和他们的学生团队将在杰斐逊实验室散射来自质子和中子的电子，以测量核子的电和磁性质，这代表了夸克和胶子在核子内部的位置。该小组通过设计新的实验，建造先进的粒子探测器，以及开发新的分析、建模和数据采集软件，为这些努力做出了贡献。PI为本科生和研究生提供有意义的实质性项目。在这些具有挑战性的项目中，PI对学生的指导使学生为STEM职业生涯做好准备。这个小组长期建立的实验计划体现了杰斐逊实验室的基本使命：阐明质子、中子和介子的基本结构。他们专注于实验，这些实验将进一步加深我们对非微扰区中质子和中子的夸克自旋结构的理解。随着这项计划使用杰斐逊实验室最近委托使用的12GeV电子束向前推进，该小组准备利用扩大的物理覆盖范围。和平研究所继续领导工作，将质子和中子电磁形状因数的测量扩大到杰斐逊实验室尽可能高的动量传递，并调查核介质内质子形状因数比的可能修改。这些实验为现有的核子结构理论模型提供了强有力的测试，同时也推动了基于量子色动力学(QCD)的新的和更先进的模型的发展。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Measurement of the proton spin structure at long distances

• DOI: 10.1038/s41567-021-01198-z
• 发表时间: 2021-02
• 期刊: Nature Physics
• 影响因子: 19.6
• 作者: X. Zheng;A. Deur;H. Kang;S. Kuhn;M. Ripani;J. Zhang;K. Adhikari;S. Adhikari;M. Amaryan;H. Atac;H. Avakian;L. Barion;M. Battaglieri;I. Bedlinskiy;F. Benmokhtar;A. Bianconi;A. Biselli;S. Boiarinov;M. Bondí;F. Bossu;P. Bosted;W. Briscoe;J. Brock;W. Brooks;D. Bulumulla;V. Burkert;C. Carlin;D. Carman;J. Carvajal;A. Celentano;P. Chatagnon;T. Chetry;J. Chen;S. Choi;G. Ciullo;L. Clark;P. Cole;M. Contalbrigo;V. Crede;A. D’Angelo;N. Dashyan;R. Vita;M. Defurne;S. Diehl;C. Djalali;V. Drozdov;R. Dupré;M. Ehrhart;A. Alaoui;L. Elouadrhiri;P. Eugenio;G. Fedotov;S. Fegan;R. Fersch;A. Filippi;T. Forest;Y. Ghandilyan;G. Gilfoyle;K. Giovanetti;F. Girod;D. Glazier;R. Gothe;K. Griffioen;M. Guidal;N. Guler;L. Guo;K. Hafidi;H. Hakobyan;M. Hattawy;T. Hayward;D. Heddle;K. Hicks;A. Hobart;T. Holmstrom;M. Holtrop;Y. Ilieva;D. Ireland;E. Isupov;H. Jo;K. Joo;S. Joosten;C. Keith;D. Keller;A. Khanal;M. Khandaker;C. W. Kim;W. Kim;F. Klein;Á. Kripkó;V. Kubarovsky;L. Lanza;M. Leali;P. Lenisa;K. Livingston;E. Long;I. Macgregor;N. Markov;L. Marsicano;V. Mascagna;B. Mckinnon;D. Meekins;T. Mineeva;M. Mirazita;V. Mokeev;C. Mullen;P. Nadel-Turonski;K. Neupane;S. Niccolai;M. Osipenko;A. Ostrovidov;M. Paolone;L. Pappalardo;K. Park;E. Pasyuk;W. Phelps;S. Phillips;O. Pogorelko;J. Poudel;Y. Prok;B. Raue;J. Ritman;Alessandro Rizzo;G. Rosner;P. Rossi;J. Rowley;F. Sabatié;C. Salgado;A. Schmidt;R.A.Schumacher;M.L.Seely;Y.G.Sharabian;U.Shrestha;S.Sirca;K. Slifer;N. Sparveris;S. Stepanyan;I. Strakovsky;S. Strauch;V. Sulkosky;N. Tyler;M. Ungaro;L. Venturelli;H. Voskanyan;E. Voutier;D. Watts;X. Wei;L. Weinstein;M. Wood;B. Yale;N. Zachariou;Z. Zhao