Precision Measurements and Fundamental Symmetries

精密测量和基本对称性

• 批准号: 1812314
• 负责人: Timothy Chupp
• 金额: $ 54万
• 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: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2023-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1812314&HistoricalAwards=false
• 关键词: Precision; Measurements; Fundamental; Symmetries

The research supported by this award will test precise Standard Model predictions and can provide solid signals of new physics by 1) measuring the magnetic signature of the muon, an exotic elementary particle that is produced in abundance at the Fermi National Accelerator Laboratory and 2) studying the detailed behavior of neutrons as they decay. This work addresses the deepest questions that we can ask: what is matter made of, how did it come to be, and how does it interact. At the same time this work addresses the technical demands of the two experiments by pushing the limits of magnetic field measurements. Many potential additional applications of these techniques may be extended into biology, neuroscience and medicine. This research provides challenging research projects for graduate and undergraduate students at the University of Michigan. A diverse cohort of graduate students are working on aspects of this research and will join former students in contributing to the National interest as teachers, researchers in physics and biomedical fields and leaders in industry.This research consists of advancing two precision measurements: the muon magnetic moment anomaly g - 2 and the beta-neutrino asymmetry parameter in neutron decay. These address the deepest question in elementary particle and nuclear physics, namely what lies beyond the Standard Model, by putting precise predictions to the test in systems most sensitive to new physics. This University of Michigan group is contributing to the Fermilab Muon g-2 experiment, which is completing the first production data run with the goal of equaling the experimental precision of the previous measurement with much better control and understanding of the systematic errors, and preparing for the upcoming data runs with the goal of improving the experimental precision by a factor of four. More specifically, the group has developed critical innovations for precision measurement of the magnetic field and its absolute calibration, and innovations in the most challenging aspect of the analysis of the field-measurement data, namely interpolating between calibration runs to track changes in the magnetic field and its spatial variations. The group will also complete commissioning and begin Nab, a new precision measurement of the beta-neutrino asymmetry parameter a in neutron decay that also probes physics Beyond the Standard Model by way of redundantly measuring the parameter lambda, the ratio of axial vector to vector coupling constants, which is also determined by the beta asymmetry (A). The neutron spin flipper designed and built at Michigan has been moved to the Fundamental Neutron Physics Beam (FNPB) at the SNS at ORNL. This will be used in determining the residual neutron beam polarization that would present a major systematic correction to the measurements. The He-3 magnetometer for absolute calibration developed and built by this group is fully operational, has sensitivity of sub ppb (part-per-billion) and will potentially impact precision magnetic field measurements from geology to medicine to physics. This research will continue to seed a number of outreach opportunities including public lectures on physics and its applications, undergraduate course development, lectures for specialist students such as the National Nuclear Physics Summer schools.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.

该奖项支持的研究将测试精确的标准模型预测，并可以通过1）测量MUON的磁性特征来提供新物理学的固体信号，MUON的磁性特征是一种外来的基本粒子，在Fermi国家加速器实验室中产生了丰度，并且2）研究中性子的详细行为衰减。这项工作解决了我们可以提出的最深层问题：什么是构成的，它是如何产生的以及它如何相互作用。同时，这项工作通过按下磁场测量的极限来解决这两个实验的技术需求。 这些技术的许多潜在应用可能会扩展到生物学，神经科学和医学中。 这项研究为密歇根大学的研究生和本科生提供了具有挑战性的研究项目。 A diverse cohort of graduate students are working on aspects of this research and will join former students in contributing to the National interest as teachers, researchers in physics and biomedical fields and leaders in industry.This research consists of advancing two precision measurements: the muon magnetic moment anomaly g - 2 and the beta-neutrino asymmetry parameter in neutron decay.这些解决了基本粒子和核物理学中最深的问题，即通过对最敏感的新物理学的系统进行确切的预测，即超出标准模型。 密歇根大学集团为Fermilab Muon G-2实验做出了贡献，该实验正在完成第一个生产数据运行，目的是等同于先前测量的实验精度，并更好地控制系统错误，并准备对即将到来的数据运行的准备，以通过四个因子来改进实验精确度。 更具体地说，该小组开发了关键的创新，以精确测量磁场及其绝对校准，以及对现场测量数据分析最具挑战性的方面的创新，即校准之间的插值以跟踪磁场及其空间变化的变化。 该小组还将完成调试并开始NAB，NAB是中子衰变中β-中性不对称参数A的新精确度量，该参数还通过重新测量参数lambda（轴向矢量与向量辅助常数的比率）来探测超出标准模型的物理学。在密歇根州设计和建造的中子旋转脚钳已移至ORNL SNS的基本中子物理束（FNPB）。这将用于确定将对测量值进行重大系统校正的残留中子束极化。 该组开发和建造的用于绝对校准的HE-3磁力计具有全部运行，具有sub ppb的灵敏度（每十亿美元），并可能影响从地质到医学到物理学的精确磁场测量值。 这项研究将继续为许多外展机会播种，包括有关物理及其应用的公开演讲，本科课程的发展，针对国家核物理暑期学校的专业学生的讲座。这项奖项反映了NSF的法定任务，并被视为值得通过基金会的知识分子和更广泛影响的评估来通过评估来提供支持。

项目成果

High-accuracy absolute magnetometry with application to the Fermilab Muon g-2 experiment

高精度绝对磁力测量法在费米实验室 Muon g-2 实验中的应用

• DOI: 10.1088/1748-0221/16/12/p12041
• 发表时间: 2021
• 期刊: Journal of Instrumentation
• 影响因子: 1.3
• 作者: Flay, D.;Kawall, D.;Chupp, T.;Corrodi, S.;Farooq, M.;Fertl, M.;George, J.;Grange, J.;Hong, R.;Osofsky, R.
• 通讯作者: Osofsky, R.

Electric dipole moments of atoms, molecules, nuclei, and particles

• DOI: 10.1103/revmodphys.91.015001
• 发表时间: 2019-01-04
• 期刊: REVIEWS OF MODERN PHYSICS
• 影响因子: 44.1
• 作者: Chupp, T. E.;Fierlinger, P.;Singh, J. T.
• 通讯作者: Singh, J. T.

Beam dynamics corrections to the Run-1 measurement of the muon anomalous magnetic moment at Fermilab

• DOI: 10.1103/physrevaccelbeams.24.044002
• 发表时间: 2021-04-27
• 期刊: PHYSICAL REVIEW ACCELERATORS AND BEAMS
• 影响因子: 1.7
• 作者: Albahri, T.;Anastasi, A.;Wu, W.
• 通讯作者: Wu, W.

Frequency shifts in noble-gas comagnetometers

• DOI: 10.1103/physreva.100.012502
• 发表时间: 2018-07
• 期刊: Physical Review A
• 影响因子: 2.9
• 作者: W. Terrano;J. Meinel;N. Sachdeva;T. Chupp;S. Degenkolb;P. Fierlinger;F. Kuchler;J. Singh

Abrasion-fission reactions at intermediate energies

• DOI: 10.1103/physrevc.108.034604
• 发表时间: 2023-09
• 期刊: Physical Review C
• 影响因子: 3.1
• 作者: M. Bowry;O. Tarasov;J. Berryman;V. Bader;Dominique Bazin;T. Chupp;H. Crawford;A. Gade;E. Lunderberg;A. Ratkiewicz;F. Recchia;B. Sherrill;D. Smalley;A. Stolz;Steven Ragnar Stroberg;D. Weisshaar;S. Williams;K. Wimmer;J. Yurkon