Analysis and Operations for the Precision Measurement of the Muon Anomaly

该奖项支持国际和平研究所在伊利诺伊州芝加哥的费米国家加速器设施进行的muon g-2实验。该实验的目标是精确测量介子对强磁场的反常响应。介子的反常磁矩来自于存在于太空中的虚拟粒子的“量子泡沫”。这一反常现象可以被精确测量，准确的结果解决了之前的测量和介子反常磁性的理论计算之间的有趣的差异-这种差异暗示了未知的力或新的自然界粒子。PI小组在实验中的责任是操作和维护实验的数据采集系统，以及提取Muon反常进动频率的数据分析-决定反常磁性的测量量。该奖项通过参与和培训高中生、物理专业的学生、研究生和博士后研究人员提供更广泛的影响。该小组参与大规模数据采集、分析和建模，也让学生接触到创新的计算机和电信技术。此外，这项实验本身--涉及教科书数量的精确测量--将在核物理、粒子和天体物理学中产生广泛的影响和持久的影响。Muon g-2实验将测量Muon反常磁矩到140 ppb；比之前的BNL E821实验提高了四倍。该测量将解决之前BNL E821测量与标准模型预测之间长期存在的约3.6标准偏差。它代表了对标准物理模型的一次关键测试，并对标准模型以外的新相互作用、粒子和现象具有广泛的敏感性。第一次数据运行发生在2017年11月至2018年7月，并于2021年4月发布。这个最初的460 ppo的测量结果与早先BNL E821实验的540 ppb结果是一致的，并将实验和标准模型之间的偏差增加到4.2标准偏差。该团队预计，从尚未分析的运行中收集的数据中，可以提高两倍，而在未来的实验中，可以提高四倍。该奖项将支持涉及费米实验室g-2实验的实验操作、数据获取和数据分析活动的持续研究。PI小组负责20 Gbyte/sec、100 TFLOP、g-2数据读出和处理系统及其升级的开发和操作。Pi小组还负责对Muon反常进动频率的积分能量分析。与传统的正电子计数方法相比，这种新的频率提取技术使用不同的原始数据，采用不同的重建程序，并且继承了不同的系统不确定性，对于证明频率测量的稳健性是重要的。最后，PI将作为分析协调员继续他在异常频率团队中的全面领导。这一奖项反映了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。

This award supports research by the PI with the muon g-2 experiment at Fermi National Accelerator Facility in Chicago, Illinois. The goal of the experiment is a precision measurement of the anomalous response of the muon to a strong magnetic field. The anomalous magnetic moment of the muon comes from the `quantum foam' of virtual particles that exists in empty space. The anomaly can be measured precisely and the exact result addresses an intriguing discrepancy between prior measurements and the theoretical calculation of the muon's anomalous magnetism - a discrepancy that hints at unknown forces or new particles of nature. The PI group's responsibilities within the experiment are the operation and maintenance of the experiment's data acquisition system and the data analysis for the extraction of the muon anomalous precession frequency - the measured quantity that determines the anomalous magnetism.The award provides a broader impact through the involvement and training of high school students, physics majors, graduate students and post-doctoral researchers. The group's involvement in large-scale data acquisition, analysis and modeling also exposes students to innovative computer and telecommunications technologies. Moreover, the experiment itself - involving a precision measurement of a textbook quantity - will have a broad impact and a lasting legacy in nuclear, particle and astrophysics.The muon g-2 experiment will measure the muon anomalous magnetic moment to 140 parts-per-billion; a four-fold improvement over the prior BNL E821 experiment. The measurement will address the longstanding ~3.6 standard deviation discrepancy between the previous BNL E821 measurement and the Standard Model prediction. It represents a key test of the Standard Model of Physics and has broad sensitivity to new interactions, particles and phenomenon beyond the Standard Model. The first data taking run took place from November, 2017 through July, 2018 and was published in April, 2021. This initial 460 part-per-billion measurement is in agreement with the earlier 540 part-per-billion result from the BNL E821 experiment and increased the discrepancy between experiment and standard model to 4.2 standard deviations. The team expects a factor of two improvement from the data collected in runs that have not yet been analyzed and a factor of four improvement from future runs of the experiment. This award will support continuing research involving activities in experimental operations, data acquisition and data analysis on the Fermilab g-2 experiment. The PI's group is responsible for the development and the operation of the 20 GByte/sec, 100 TFlop, g-2 data readout and processing system and its upgrades. The PI's group is also responsible for the integrated energy analysis of the muon anomalous precession frequency. This new technique for extracting the frequency uses different raw data, applies different reconstruction procedures, and inherits different systematic uncertainties, in comparison to the traditional positron counting approaches and is important to the demonstration of the robustness of the frequency measurement. Lastly, the PI will continue his overall leadership in the anomalous frequency team as an analysis coordinator.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.