RUI-Meson Spectroscopy with GlueX and CLAS12 at Jefferson Lab

尽管当前的核物理和粒子物理理论总体上取得了巨大的成功，但该模型的某些部分缺乏定量的理解。其中一个部分是强力产生各种各样的粒子的方式，这些粒子被称为“强子”(质子、中子、…以及质量较小的“介子”)。由所谓的量子色动力学(QCD)描述的这种强大的力也是大多数核结构和反应的原因。该奖项支持诺福克州立大学(NSU)的一名教授和两名本科生作为GlueX和MesonEx(CLAS12)实验的成员参与位于弗吉尼亚州纽波特纽斯的托马斯·杰斐逊国家加速器设施的强大作用力研究。这项研究计划旨在识别QCD预测的亚原子粒子的新形式，这些粒子可以极大地有助于理解这种强大的作用力。这些“异类”是一种强大的力量的表现，否则这种力量就隐藏在强子内部并被限制在其中。北卡罗来纳州立大学的教职员工和本科生已经开发了进行这些研究的软件和硬件。最近，他们开发了新的软件，用于分析通过这些实验获得的大数据集。该奖项将通过包括机器学习技术的最新进展、探索新的统计技术、计算机硬件选择和软件编程语言来继续这些发展。他们还将参与对两个实验已经收集的数据的分析。NSU校区靠近杰斐逊实验室，为NSU的学生提供了全年参与研究的机会。该项目的一个目标是加强代表不足的少数群体对核物理和粒子物理研究的参与。历史上，黑人学院和大学(HBCU)，如NSU，在留住少数族裔学生在本科生水平并将他们引入STEM学科的研究生课程方面一直非常成功。介子能谱对于理解中能级强相互作用具有重要意义，目的是找到关于QCD禁闭的细节。这个项目建议继续诺福克州立大学(NSU)在杰斐逊实验室的GlueX(D厅)和MesonEx(CLAS12-B厅)实验中参与介子谱。NSU参与了这两个实验的硬件建设和软件开发，并参与了之前与介子光产生有关的CLAS6(JLab-Hall B)实验的数据分析。NSU小组将从GlueX和CLAS12(MesonEx)已经收集的数据中参与对介子最终状态的分析。他们还将继续软件开发，特别是执行少数几个物体最终状态的完整部分波分析(PWA)所需的软件。接下来的几年将是对GlueX和MesonEx Run的数据分析得出结论的时候，这两个数据都探索了奇异强子的产生，并扩展了目前的介子光谱。在过去的几年里，PI和NSU的学生一直在参与PWA的软件框架的开发，称为PyPWA。他们一直在与JLab(JPAC)的理论小组成员、CLAS12和GlueX的合作者合作，为介子光谱研究开发出更高效、用户友好和快速的分析代码。GlueX和MesonEx已经获得了比以前的光谱实验具有更好的系统和统计不确定性的数据，并暴露了以前现有分析方法的局限性。在理论家(模型)和实验者(软件)之间以及重子和介子光谱小组之间的密切合作下，需要进行新的改进。具体地说，对最终状态Δ++𝛈𝛑(寻找异域生物)和p𝜑𝛈(奇异状态)的研究将由南加州大学的学生在PI的监督下进行。软件开发将包括利用新的硬件(即使用CUDA的图形处理器)和软件(即人工智能(AI)模式识别方法，如贝叶斯神经网络(BNN))。该项目将使南加州大学的教职员工和本科生有机会参与对核物理研究前沿实验数据的分析。北卡罗来纳州立大学是国内领先的HBCU之一，其主校区距离杰斐逊实验室很近。PI在杰斐逊实验室涉及少数族裔学生的记录由来已久。该奖项将继续为代表性不足的少数群体提供机会，并加强核物理研究的多样性。该奖项反映了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。

In spite of the overall great success of the current theory of nuclear and particle physics, some sectors of this model lack quantitative understanding. One such sector is the way the strong force produces the wide variety of particles called “hadrons” (protons, neutrons,…and the less massive “mesons”). The strong force, described by what is called Quantum-Chromodynamics (QCD), is also responsible for most of nuclear structure and reactions. This award supports a professor and two undergraduate students from Norfolk State University (NSU) to participate in the study of the strong force as members of the GlueX and MesonEx (CLAS12) experiments at the Thomas Jefferson National Accelerator Facility located in Newport News, Virginia. The research program aims to identify new forms of sub-atomic particles (“exotics”), predicted by QCD, that can greatly contribute to the understanding of the strong force. These “exotics” are a manifestation of the strong force that otherwise is hidden and confined inside the hadrons. NSU faculty and undergraduate students have developed software and hardware to perform these studies. More recently they have developed new software for the analysis of big data sets obtained by those experiments. This award will continue those developments by including the latest advances in machine learning techniques, exploring new statistical techniques, computer hardware options and software programing languages. They will also participate in the analysis of data already collected by both experiments. The NSU campus is close to Jefferson Lab, providing NSU students opportunities to participate in research all year around. A goal of this project is to strengthen the participation of underrepresented minorities in nuclear and particle physics research. Historically Black Colleges and Universities (HBCU), such as NSU, have been very successful in retaining minority students at the undergraduate level and introducing them to graduate programs in STEM disciplines. Meson spectroscopy is of fundamental importance for the understanding of the strong interaction at intermediate energies with the goal of finding details about QCD confinement. This project proposes to continue Norfolk State University’s (NSU) participation on Meson Spectroscopy at the GlueX (Hall D) and MesonEx (CLAS12-Hall B) experiments at Jefferson Lab. NSU had been involved in hardware construction and software development for both experiments, and in the data analysis of previous CLAS6 (JLab-Hall B) experiments related to meson photo-production. The NSU group will be involved in the analyses of the meson’s final states from data already collected by GlueX and CLAS12 (MesonEx). They will also continue software development, in particular, the necessary software to perform full Partial Wave Analysis (PWA) of few body final states. The next couple of years will be the time to bring to a conclusion the analysis of data from GlueX and MesonEx runs, both exploring the production of exotic hadrons and expanding on current meson spectroscopy. The PI and NSU students have been involved in the development of a software framework for PWA, called PyPWA, for the last several years. They have been working in collaboration with members of the theory group at JLab (JPAC), collaborators from CLAS12 and GlueX to produce a more efficient, user friendly and fast analysis code for the study of meson spectroscopy. GlueX and MesonEx have obtained data with much better systematic and statistical uncertainties then previous spectroscopy experiments and exposed the limitations of the previously existing methods of analysis. New refinements are required with a close collaboration between theorists (models) and experimentalists (software) and between baryon and meson spectroscopy groups. Specifically, studies of the final states Δ++𝛈𝛑 (search for exotics) and p𝜑𝛈 (strangeonia) will be performed by NSU’s students under the PI’s supervision. Software developments will include the utilization of new hardware (i.e. GPUs using CUDA) and software (i.e. Artificial Intelligence (AI) methods of pattern recognition, as Bayesian Neural Networks - BNN). This project will allow NSU’s faculty and undergraduate students the opportunity to participate in the analysis of data from experiments at the forefront of nuclear physics research. NSU is one of the leading HBCU’s in the country and its main campus is conveniently located at a short distance from Jefferson Lab. The PI has a long record of involving minority students at Jefferson Lab. This award will continue to provide opportunities to underrepresented minorities and strengthen diversity in nuclear 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.