NSF-BSF: Searching for Physics Beyond the Standard Model at the LHCb Experiment

NSF-BSF：在 LHCb 实验中寻找超越标准模型的物理学

• 批准号: 1912836
• 负责人: Mike Williams
• 金额: $ 45万
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-07-01 至 2022-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1912836&HistoricalAwards=false
• 关键词: NSF; BSF; Searching; Physics; Beyond

One of the major intellectual achievements of the 20th century was the development of the Standard Model (SM) of particle physics. This model succeeded in classifying all of the elementary particles known at the time into a hierarchy of groups having similar quantum properties. The validity of this model to date was confirmed by the discovery of the Higgs boson at the Large Hadron Collider at CERN. However, the Standard Model as it currently exists, leaves open many questions about the universe. These include why matter dominates over anti-matter in the Universe (CP violation), the values of the masses of the fundamental constituents, the quarks and the leptons, the size of the mixings among the quarks, and separately among the leptons, and the properties of dark matter. Most explanations require the presence of new particles, symmetries or forces, which we call Beyond the Standard Model Physics (BSM). This project is designed to pursue searches for BSM physics. The LHC is the premier High Energy Physics particle accelerator in the world and is currently operating at the CERN laboratory near Geneva Switzerland, one of the foremost facilities for answering these BSM questions. The Massachusetts Institute of Technology group is a collaboration member of LHCb, an experiment designed specifically to study the decays of hadrons containing b or c quarks at the LHC and to search for other new states of matter. The goal of LHCb is to identify new physics in nature by examining the properties of hadrons containing these quarks. New physics, or new forces, can be manifest by particles, as yet to be discovered, whose presence would modify decay rates and CP violating asymmetries of hadrons containing the b and c quarks, and thus allow new phenomena to be observed indirectly. Additionally, LHCb is making contributions to the study of the emergent phenomenology of quantum chromodynamics (QCD), and to searches for new GeV-scale (i.e. "low mass") BSM particles, possibly components of the dark sector of matter. And it is in this research domain that the MIT group is playing a leading and fundamental role, both in the development of new trigger strategies based upon machine learning algorithms to identify and select the physics of interest, but also in conducting analyses of interactions that might contain hypothetical "dark sector" particles such as dark photons or axion-like particles. The analytical activities associated with these dark sector studies are enhanced in this program through collaboration with Technion in Israel, through the United States - Israel Binational Science Foundation (NSF-BSF) program.The machine learning algorithms developed by the MIT-LHCb group are available in open-source software packages and are being used by many other research groups. Additionally, the group has introduced at MIT the well-recognized International Masterclasses program, which brings local high school students to the MIT campus to learn about the excitement of high energy physics research.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.

20世纪的主要知识成就之一是粒子物理学标准模型（SM）的发展。该模型成功地将当时已知的所有基本粒子分类为具有相似量子特性的组的层次结构。迄今为止，通过发现Higgs玻色子在CERN的大型强子对撞机上发现了该模型的有效性。但是，目前存在的标准模型留下了有关宇宙的许多问题。其中包括为什么物质在宇宙中占主导地位（违反CP），基本成分质量的值，夸克和叶子的质量，夸克之间的混合大小以及卵子中的混合大小，在lept子中分别以及暗物质的性质。大多数解释都需要存在新的粒子，对称性或力，我们将其称为标准模型物理（BSM）。该项目旨在追求BSM物理学的搜索。 LHC是世界上首要的高能物理粒子加速器，目前在瑞士日内瓦附近的CERN实验室运营，这是回答这些BSM问题的最重要设施之一。马萨诸塞州理工学院集团是LHCB的合作成员，该实验专门研究LHC在LHC上包含B或C Quarks的Hadron的衰减，并搜索其他新的物质状态。 LHCB的目的是通过检查包含这些夸克的Hadron的特性来识别自然界的新物理学。新的物理学或新力可以通过颗粒表现出来，尚待发现，其存在会改变腐烂的速率和违反包含B和C夸克的Hadron的CP，因此可以间接观察到新现象。此外，LHCB还为研究量子染色体动力学（QCD）的新兴现象学做出贡献，并搜索新的GEV尺度（即“低质量”）BSM颗粒，可能是物质黑暗扇形的组成部分。 在这个研究领域，麻省理工学院组在基于机器学习算法的新触发策略中发挥了领导和基本作用，以识别和选择感兴趣的物理学，而且在进行可能包含假设“黑暗扇区”粒子（例如黑暗光子或轴突般的类似轴突的颗粒）的相互作用的分析中。 通过与以色列的技术合作通过美国 - 以色列双性科学基金会（NSF-BSF）计划，该计划中与这些黑暗部门研究相关的分析活动得到了增强。MIT-LHCB组开发的机器学习算法在开放源软件包中可用，并被许多其他研究小组使用。 此外，该小组还在MIT介绍了公认的国际大师班计划，该计划将当地的高中生带到了MIT校园，以了解高能物理学研究的兴奋。该奖项反映了NSF的法定任务，并认为通过基金会的知识分子和更广泛的影响，通过评估值得通过评估来进行支持。

项目成果

Enhancing searches for resonances with machine learning and moment decomposition

• DOI: 10.1007/jhep04(2021)070
• 发表时间: 2020-10
• 期刊: Journal of High Energy Physics
• 影响因子: 5.4
• 作者: O. Kitouni;B. Nachman;C. Weisser;Mike Williams

Identification of charm jets at LHCb

LHCb 魅力喷流的识别

• DOI: 10.1088/1748-0221/17/02/p02028
• 发表时间: 2022
• 期刊: Journal of Instrumentation
• 影响因子: 1.3
• 作者: Aaij, R.;Abdelmotteleb, A.S.W.;Abellán Beteta, C.;Abudinen Gallego, F.J.;Ackernley, T.;Adeva, B.;Adinolfi, M.;Afsharnia, H.;Agapopoulou, C.;Aidala, C.A.
• 通讯作者: Aidala, C.A.

Searches for low-mass dimuon resonances

• DOI: 10.1007/jhep10(2020)156
• 发表时间: 2020-10-26
• 期刊: JOURNAL OF HIGH ENERGY PHYSICS
• 影响因子: 5.4
• 作者: Aaij, R.;Beteta, C. Abellan;Zunica, G.
• 通讯作者: Zunica, G.

Searches for Dark Photons at Accelerators

在加速器中搜索暗光子

• DOI: 10.1146/annurev-nucl-110320-051823
• 发表时间: 2021
• 期刊: Annual Review of Nuclear and Particle Science
• 影响因子: 12.4
• 作者: Graham, Matt;Hearty, Christopher;Williams, Mike
• 通讯作者: Williams, Mike