Studying Quantum Chromodynamics at LHCb

在 LHCb 研究量子色动力学

• 批准号: 2012926
• 负责人: Christine Aidala
• 金额: $ 55.52万
• 依托单位: Regents of the University of Michigan - Ann Arbor
• 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: 2020-07-01 至 2023-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2012926&HistoricalAwards=false
• 关键词: Studying; Quantum; Chromodynamics; LHCb

The protons and neutrons in the atomic nuclei of everyday matter are made of subnuclear particles called quarks and gluons. The project supported by this award will study how quarks and gluons scattered out of a proton or produced in high-energy particle collisions subsequently form new bound states. Additional measurements will investigate how strong nuclear charge, called color, flows through proton-proton scattering processes, searching for a theoretically predicted novel state of quarks and gluons that exhibit quantum correlations across colliding protons. Data from the Large Hadron Collider at the European Organization for Nuclear Research (CERN) will be used to perform the research, as part of the Large Hadron Collider Beauty (LHCb) experiment. The research performed will advance our understanding of how strong force bound states such as protons can be created, and the dynamics of their possible interactions. The project supported by this award will furthermore train early career scientists from diverse backgrounds in nuclear physics. Training the next generation of nuclear physicists is critical to maintain expertise relevant to the nation's energy and defense needs and to continue advancing both applied and non-applied research in nuclear physics and technology. Specifically, this award will enable mentored research in nuclear physics on the LHCb experiment by a woman postdoctoral scholar and four Ph.D. students, two women and two men, of which one is Latina American and another African American. In the third year of the award, a student from Mount Holyoke College, an undergraduate institution for women, will have the opportunity to perform summer research in nuclear physics at the University of Michigan.The PI’s group will study how high-energy color-charged quarks hadronize into sprays of observable color-neutral bound states by performing a suite of complementary measurements at LHCb. Specifically, the measurements will compare charged hadron distributions in jets initiated predominantly by light versus heavy quarks; examine evidence for contributions from string breaking versus quark recombination models of hadronization via measurements of baryon versus meson production as a function of event multiplicity; and study spin-momentum correlations in hadronization by measurement of spontaneous polarization of produced hyperons. The proposed hadronization program will contribute toward the ultimate, long-term goal of being able to predict statistically the fully correlated distributions of particles from different flavor high-energy fragmenting quarks. Separate measurements will explore the role of color flow in hadronic scattering processes by searching for experimental evidence of transverse-momentum-dependent factorization breaking and color entanglement. The specific observables include correlated production of nearly back-to-back Z boson-hadron, hadron-hadron, and Z boson-jet pairs. The activities furthermore include contributions to the installation, commissioning, and maintenance of the U.S.-led Upstream Tracker silicon detector upgrade for LHCb.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.

日常物质的原子核中的质子和中子是由称为夸克和胶子的亚核粒子组成的。 该奖项支持的项目将研究夸克和胶子如何从质子中散射出来或在高能粒子碰撞中产生，随后形成新的束缚态。 额外的测量将研究强核电荷（称为颜色）如何流过质子-质子散射过程，寻找理论上预测的夸克和胶子的新状态，这些状态在碰撞的质子之间表现出量子相关性。 来自欧洲核子研究组织（CERN）大型强子对撞机的数据将用于进行研究，作为大型强子对撞机美容（LHCb）实验的一部分。 所进行的研究将推进我们对如何创建质子等强力束缚态以及它们可能相互作用的动力学的理解。 该奖项支持的项目将进一步培养来自不同背景的核物理学早期职业科学家。培养下一代核物理学家对于保持与国家能源和国防需求相关的专业知识以及继续推进核物理和技术的应用和非应用研究至关重要。 具体而言，该奖项将使一名女博士后学者和四名博士生能够指导LHCb实验的核物理研究。学生，两名妇女和两名男子，其中一名是拉丁美洲人，另一名是非洲裔美国人。 在该奖项颁发的第三年，一名来自女子本科院校蒙特霍利奥克学院的学生将有机会在密歇根大学进行夏季核物理研究。PI的小组将通过在LHCb进行一系列补充测量来研究高能色荷夸克如何强子化为可观察的色中性束缚态喷雾。 具体而言，测量将比较主要由轻夸克和重夸克引发的喷流中的带电强子分布;通过测量重子与介子的产生作为事件多重性的函数，检查强子化的弦断裂与夸克重组模型的贡献的证据;通过测量产生的超子的自发极化，研究强子化中的自旋动量相关性。 建议的强子化计划将有助于实现最终的，长期的目标，能够统计预测完全相关的粒子分布从不同的味道高能碎裂夸克。 单独的测量将探索色流在强子散射过程中的作用，通过寻找横向动量相关因子分解破缺和色纠缠的实验证据。 具体的观测量包括相关产生的近背靠背Z玻色子-强子，强子-强子，和Z玻色子喷注对。 这些活动还包括对美国-该奖项反映了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

Measurement of flavor asymmetry of the light-quark sea in the proton with Drell-Yan dimuon production in p+p and p+d collisions at 120 GeV

利用 120 GeV 的 p p 和 p d 碰撞中的 Drell-Yan 低介子产生来测量质子中轻夸克海的味道不对称性

• DOI: 10.1103/physrevc.108.035202
• 发表时间: 2023
• 期刊: Physical Review C
• 影响因子: 3.1
• 作者: Dove, J.;Kerns, B.;Leung, C.;McClellan, R. E.;Miyasaka, S.;Morton, D. H.;Nagai, K.;Prasad, S.;Sanftl, F.;Scott, M. B.
• 通讯作者: Scott, M. B.

The asymmetry of antimatter in the proton

• DOI: 10.1038/s41586-021-03282-z
• 发表时间: 2021-02
• 期刊: Nature
• 影响因子: 64.8
• 作者: J. Dove;B. Kerns;R. McClellan;S. Miyasaka;D. H. Morton;K. Nagai;S. Prasad;F. Sanftl;M. Scott;A. Tadepalli;C. Aidala;J. Arrington;C. Ayuso;C. L. Barker;C. Brown;W. Chang;A. Chen;D. Christian;B. Dannowitz;M. Daugherity;M. Diefenthaler;L. El Fassi;D. Geesaman;R. Gilman;Y. Goto;L. Guo;R. Guo;T. Hague;R. Holt;D. Isenhower;E. Kinney;N. Kitts;A. Klein;D. Kleinjan;Y. Kudo;Ching Him Leung;P. Lin;K. Liu;M. Liu;W. Lorenzon;N. Makins;M. D. de Medeiros;P. McGaughey;Y. Miyachi;I. Mooney;K. Nakahara;K. Nakano;S. Nara;J. Peng;A. Puckett;B. Ramson;P. Reimer;J. Rubin;S. Sawada;T. Sawada;T. Shibata;D. Su;M. Teo;B. Tice;R. Towell;S. Uemura;S. Watson;S. Wang;A. Wickes;J. Wu;Z. Xi;Z. Ye

Ntuple Wizard: An Application to Access Large-Scale Open Data from LHCb

Ntuple Wizard：从 LHCb 访问大规模开放数据的应用程序

• DOI: 10.1007/s41781-023-00099-5
• 发表时间: 2023
• 期刊: Computing and Software for Big Science
• 作者: Aidala, Christine A.;Burr, Christopher;Cattaneo, Marco;Fitzgerald, Dillon S.;Morris, Adam;Neubert, Sebastian;Tropmann, Donijor
• 通讯作者: Tropmann, Donijor