Precision Measurement of Coherent Elastic Neutrino-Nucleus Scattering from Reactor Antineutrinos

相干弹性中微子-核散射(CEvNS)是最近发现的一种中微子相互作用模式。可能的技术应用包括核反应堆监测。CEVNS还为研究中微子的性质和核结构提供了一个新的灵敏窗口。该合同将允许在动力核反应堆(低能中微子的强源)附近安装CEVNS敏感探测器，首次观察CEVNS信号与反应堆功率之间的关系。将探测到的信号与理论模型的预期进行比较，将约束目前尚不为人所知的几种中微子性质。如果观察到与粒子相互作用标准模型预测的偏差，将形成能够取代这一当前理论框架的新模型。该奖项还将促进使用能够模拟CEVNS信号的中子束进行探测器校准：这些研究对于解释反应堆暴露期间获得的数据是必要的。将为研究生获得博士学位提供支持，重点是招募西班牙裔少数族裔。之前的国家科学基金会支持(PHY-1506357和PHY-1812702)允许PI和他的团队在散裂源进行第一次CEVN测量，并使用靠近德累斯顿-II核反应堆核心的超低噪声、大质量锗探测器从反应堆反中微子获得这一过程的提示性证据。该奖项将在布雷德伍德发电站的一个地下肌腱画廊继续这一努力。这一位置将使信号背景比从目前获得的1/4提高到20，在此过程中产生CEνNS的高质量精确测量，而不依赖于背景模型假设。这将最大限度地提高探测器开发和分析工具方面已经做出的努力的回报。此外，俄亥俄州立大学研究校长将利用该设施过去的经验，对锗中核反冲的亚keV猝灭因子进行新的测量。这两项测量的结合预计将对中微子现象的多个方面产生重大影响。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。

Coherent Elastic Neutrino-Nucleus Scattering (CEvNS) is a recently demonstrated mode of interaction for neutrinos. Possible technological applications include nuclear reactor monitoring. CEvNS also provides a new sensitive window into the study of neutrino properties and nuclear structure. This award will allow the installation of a CEvNS-sensitive detector in the vicinity of a power nuclear reactor (an intense source of low-energy neutrinos), observing for the first time the correlation between CEvNS signals and reactor power. A comparison of the signals detected with expectations from theoretical models will constrain several neutrino properties presently not well-known. Deviations from the predictions of the Standard Model of particle interactions, if observed, will inform new models capable of superseding this current theoretical framework. The award will also facilitate detector calibrations using neutron beams capable of mimicking CEvNS signals: these studies are necessary to interpret the data obtained during reactor exposure. Support for a graduate student towards Ph.D. completion will be provided, with an emphasis on the recruitment of Hispanic minorities. Previous NSF support (PHY-1506357 and PHY-1812702) allowed the PI and his team to perform the first measurement of CEvNS at a spallation source, and to obtain suggestive evidence for this process from reactor antineutrinos using an ultra-low noise, large mass germanium detector in close proximity to the core of the Dresden-II nuclear reactor. This award will continue this effort at one of the underground tendon galleries of the Braidwood Generating Station. This location will provide an improvement in signal-to-background ratio from the presently obtained 1/4 to 20, generating in the process a high-quality precision measurement of CEνNS, independent of background model assumptions. This will maximize returns on the effort already made in detector development and analysis tools. Additionally, a new measurement of the sub-keV quenching factor for nuclear recoils in germanium will be performed at the Ohio State University research rector, profiting from past experience at that facility. The combination of these two measurements is expected to have a large impact on multiple aspects of neutrino phenomenology.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.