NSF-BSF: The Study of Nuclear Physics with Intermediate Energy Probes

NSF-BSF：利用中能探针进行核物理研究

• 批准号: 1812382
• 负责人: Yordanka Ilieva
• 金额: $ 105万
• 依托单位: University of South Carolina at Columbia
• 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=1812382&HistoricalAwards=false
• 关键词: NSF; BSF; Study; Nuclear; Physics

Although ninety-eight percent of the mass of ordinary matter is due to the strong subatomic force, the present theory of that force (Quantum Chromodynamics) is still not fully understood. This award supports the study of the strong force by probing the substructure of matter. Almost the entire mass of an atom is concentrated in its tiny nucleus, which is made of nucleons that are either positively charged (protons) or electrically neutral (neutrons). These subatomic particles, however, are not elementary but are themselves composite objects made of quarks held together by glue particles (gluons). The structure of nucleons is a manifestation of the strong force, which is indeed the strongest force known. This project helps to address overarching questions about the origin of most of the visible mass in the universe, the nature of neutron stars, the properties of dense nuclear matter, and the structure of nucleons. Answering these and related questions is a complex task requiring dedicated experimental observations and careful testing of theoretical predictions against measured observations. This research will help discovery in and advance understanding of nuclear physics, and will promote teaching, training, and learning. The preparation of junior scientists plays a central role in the supported activities.The nuclear physics research program at the University of South Carolina (USC) is based at the Thomas Jefferson National Accelerator Facility (JLab) in Newport News, Virginia and the Paul Scherrer Institute (PSI) in Switzerland. At JLab, the group uses high-energy electron and photon beams along with sophisticated particle detectors, that were developed, in part, at USC, as powerful microscopes to study the structure and interaction of baryons. This research program will continue to provide crucial high-precision,polarized and unpolarized, electro- and photo-production observables that will pin down present problems in strong QCD. Complete and mostly complete meson-photoproduction measurements will settle in an almost model-independent way lingering problems in baryon spectroscopy and in particular verify the SU(6)xO(3) three quark baryon structure. Alternatively, the structure of baryons can be probed through their interactions in scattering processes. The study of strong interactions involving the strange quark is essential to understand the properties of neutron stars. This project carries a comprehensive study of hyperon photo-production off deuterons. The extensive set of single- and double-polarization observables will provide long-needed information from experiments on the hyperon-nucleon interaction. The properties of hadrons are modified in the medium as a consequence of the partial restoration of chiral symmetry and many-body effects. The bound proton electromagnetic form factors in He-4 may be modified compared to those in the vacuum as revealed for the first time by the group's earlier measurements. The upcoming USC experiment on He-4, H-2, and H-1 at JLab will confirm or refute these results. The observations of such phenomena are potentially transformative in the way we view hadrons and their interactions in nuclear matter. At PSI, the group is preparing the MUSE experiment. This precision experiment will address the proton-radius puzzle by scattering muons and electrons off the proton.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.

虽然普通物质质量的98%是由于强亚原子力，但这种力的现有理论（量子色动力学）仍然没有完全理解。该奖项支持通过探索物质的子结构来研究强作用力。原子的几乎全部质量都集中在它的微小的原子核中，原子核由带正电（质子）或电中性（中子）的核子组成。然而，这些亚原子粒子并不是基本粒子，它们本身是由夸克通过胶粒子（胶子）结合在一起而形成的复合物体。核子的结构是强力的一种表现，它确实是已知的最强的力。该项目有助于解决有关宇宙中大部分可见质量的起源，中子星的性质，致密核物质的性质以及核子结构的首要问题。解决这些问题和相关问题是一项复杂的任务，需要专门的实验观察和仔细测试的理论预测与测量观察。这项研究将有助于发现和促进对核物理的理解，并将促进教学，培训和学习。南卡罗来纳州大学的核物理研究计划设在弗吉尼亚州纽波特纽斯的托马斯杰斐逊国家加速器设施（JLab）和瑞士的保罗谢勒研究所（PSI）。在JLab，该小组使用高能电子和光子束沿着复杂的粒子探测器，这些探测器部分是在南加州大学开发的，作为强大的显微镜来研究重子的结构和相互作用。这项研究计划将继续提供关键的高精度，偏振和非偏振，电和光的生产可观的，将钉在强QCD目前的问题。完整的和基本完整的介子光生测量将以一种几乎与模型无关的方式解决重子谱学中的遗留问题，特别是验证SU（6）xO（3）三夸克重子结构。或者，重子的结构可以通过它们在散射过程中的相互作用来探测。研究涉及奇异夸克的强相互作用对于理解中子星的性质是必不可少的。本项目对氘光生超子进行了全面的研究。大量的单偏振和双偏振观测量将提供超子-核子相互作用实验中长期需要的信息。由于手征对称性的部分恢复和多体效应，强子的性质在介质中发生了变化。He-4中的束缚质子电磁形状因子与真空中的那些相比可能会被修改，这是该小组早期测量首次揭示的。即将在JLab进行的关于He-4，H-2和H-1的USC实验将证实或反驳这些结果。对这种现象的观察可能会改变我们看待强子及其在核物质中相互作用的方式。在PSI，该小组正在准备MUSE实验。这个精确的实验将通过散射质子的μ子和电子来解决质子半径之谜。这个奖项反映了NSF的法定使命，并通过使用基金会的知识价值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

Polarization transfer to bound protons measured by quasielastic electron scattering on C12

• DOI: 10.1103/physrevc.101.064615
• 发表时间: 2020-03
• 期刊: Physical Review C
• 影响因子: 3.1
• 作者: T. Brecelj;S. Paul;T. Kolar;P. Achenbach;A. Ashkenazi;R. Böhm;E. Cohen;M. Distler;A. Esser;R. Gilman;C. Giusti;D. Izraeli;I. Korover;J. Lichtenstadt;I. Mardor;H. Merkel;M. Mihovilovič;U. Müller;M. Olivenboim;E. Piasetzky;G. Ron;B. Schlimme;M. Schoth;F. Schulz;C. Sfienti;S. Širca;S. Štajner;S. Strauch;M. Thiel;A. Weber;I. Yaron

The CLAS12 Forward Time-of-Flight system

CLAS12 前向飞行时间系统

• DOI: 10.1016/j.nima.2020.163629
• 发表时间: 2020
• 期刊: Detectors and Associated Equipment
• 作者: Carman, D.S.;Clark, L.;De Vita, R.;Fedotov, G.;Gothe, R.W.;Hollis, G.;Miller, B.;Phelps, E.;Tian, Y.;Trivedi, A.
• 通讯作者: Trivedi, A.

Beam-target helicity asymmetry E in K0Λ and K0Σ0 photoproduction on the neutron

• DOI: 10.1103/physrevc.98.045205
• 发表时间: 2018-05
• 期刊: Physical Review C
• 影响因子: 3.1
• 作者: C. Ho;R. Schumacher;A. D’Angelo;A. Deur;J. Fleming;C. Hanretty;T. Kageya;F. Klein;E. Klempt;M. Lowry;H. Lu;V. Nikonov;P. Peng;A. Sandorfi;A. Sarantsev;I. Strakovsky;N. Walford;X. Wei;R. Workman;K. Adhikari;S. Adhikari;D. Adikaram;Z. Akbar;J. Ball;L. Barion;M. Bashkanov;C. Bass;M. Battaglieri;I. Bedlinskiy;A. Biselli;W. Briscoe;S. Boiarinov;V. Burkert;F. Cao;D. Carman;A. Celentano;S. Chandavar;G. Charles;P. Chatagnon;T. Chetry;G. Ciullo;B. Clary;P. Cole;M. Contalbrigo;V. Crede;R. Vita;M. Defurne;S. Diehl;C. Djalali;R. Dupré;H. Egiyan;M. Ehrhart;A. Alaoui;Lamiaa El Fassi;P. Eugenio;G. Fedotov;S. Fegan;R. Fersch;A. Filippi;A. Fradi;Y. Ghandilyan;K. Giovanetti;F. Girod;W. Gohn;E. Golovatch;R. Gothe;K. Griffioen;M. Guidal;K. Hafidi;H. Hakobyan;N. Harrison;M. Hattawy;D. Heddle;K. Hicks;M. Holtrop;Y. Ilieva;D. Ireland;B. Ishkhanov;E. Isupov;D. Jenkins;H. Jo;S. Johnston;M. Kabir;D. Keller;G. Khachatryan;M. Khachatryan;M. Khandaker;A. Kim;W. Kim;A. Klein;V. Kubarovsky;V. Lainé;L. Lanza;P. Lenisa;K. Livingston;I. Macgregor;D. Marchand;N. Markov;M. Mayer;B. Mckinnon;C. Meyer;M. Mirazita;V. Mokeev;R. Montgomery;A. Movsisyan;C. Camacho;P. Nadel-Turonski;S. Niccolai;G. Niculescu;T. O'Connell;M. Osipenko;A. Ostrovidov;M. Paolone;R. Paremuzyan;K. Park;E. Pasyuk;O. Pogorelko;J. Price;Y. Prok;D. Protopopescu;M. Rehfuss;M. Ripani;D. Riser;Alessandro Rizzo;G. Rosner;F. Sabati'e;C. Salgado;Y. Sharabian;I. Skorodumina;G. Smith;D. Sober;D. Sokhan;N. Sparveris;S. Strauch;M. Taiuti;J. Tan;M. Ungaro;H. Voskanyan;E. Voutier;R. Wang;D. Watts;L. Weinstein;C. Whisnant;M. Wood;N. Zachariou;J. Zhang;Z. Zhao;I. Zonta

The influence of Fermi motion on the comparison of the polarization transfer to a proton in elastic e→p and quasi-elastic e→A scattering

• DOI: 10.1016/j.physletb.2019.04.004
• 发表时间: 2019-01
• 期刊: Physics Letters B
• 影响因子: 4.4
• 作者: S. Paul;T. Brecelj;H. Arenhövel;P. Achenbach;A. Ashkenazi;J. Beričič;R. Böhm;D. Bosnar;E. Cohen;L. Debenjak;M. Distler;A. Esser;I. Friščić;R. Gilman;D. Izraeli;T. Kolar;I. Korover;J. Lichtenstadt;I. Mardor;H. Merkel;D. Middleton;M. Mihovilovič;M. Mihovilovič;U. Müller;M. Olivenboim;E. Piasetzky;J. Pochodzalla;G. Ron;B. Schlimme;M. Schoth;F. Schulz;C. Sfienti;S. Širca;S. Štajner;S. Strauch;M. Thiel;A. Tyukin;A. Weber;I. Yaron

12C(e,e'pN) measurements of short range correlations in the tensor-to-scalar interaction transition region

张量到标量相互作用过渡区域的短程相关性的 12C(e,epN) 测量

• DOI: 10.1016/j.physletb.2021.136523
• 发表时间: 2021
• 期刊: Physics Letters B
• 影响因子: 4.4
• 作者: Korover, I.;Pybus, J.R.;Schmidt, A.;Hauenstein, F.;Duer, M.;Hen, O.;Piasetzky, E.;Weinstein, L.B.;Higinbotham, D.W.;Adhikari, S.
• 通讯作者: Adhikari, S.