Neutrinoless Double-Beta Decay with Germanium Detectors: Majorana Demonstrator and LEGEND

使用锗探测器的无中微子双贝塔衰变：马约拉纳演示器和传奇

• 批准号: 1812409
• 负责人: Matthew Green
• 金额: $ 41.86万
• 依托单位: North Carolina State University
• 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 2022-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1812409&HistoricalAwards=false
• 关键词: Neutrinoless; Double; Beta; Decay; Germanium

The non-zero masses and neutral electric charge of neutrinos allows for the possibility that neutrinos are their own antiparticles (i.e. Majorana particles), in which case an ultra-rare form of nuclear decay known as neutrinoless double-beta decay (NLDBD) may occur. If neutrinos are shown to be Majorana particles, it would provide an explanation for the very small masses of neutrinos; point to new physics at energies beyond the reach of our most powerful colliders; and motivate an explanation for the prevalence of matter over anti-matter in the Universe. This award supports software and instrumentation research on an experiment to test the Majorana characteristics of neutrinos and the next phase experiment, called LEGEND. Both experiments use ultra-pure germanium detectors and are at the cutting edge of science. The PI will train graduate students in novel techniques that will allow them to compete in high-technology based careers. Additionally, the PI has an innovative program in outreach to the public. The LEGEND Experiment will use the ultra-pure materials developed by the MAJORANA Collaboration and the liquid cryogen active shielding developed by the GERDA Collaboration in the construction of a phased-deployment ton-scale experiment with discovery potential for NLDBD at half-lives beyond 10e28 years. This project will extend LEGEND's sensitivity to NLDBD and dark matter by building on a full understanding of the backgrounds in the MAJORANA DEMONSTRATOR and reducing backgrounds associated with cosmogenic Argon isotopes in a liquid cryogen compton veto. Specifically, the PI and his group aim to: construct a comprehensive background model of the MAJORANA DEMONSTRATOR NLDBD experiment using Monte Carlo simulations and experimental data; investigate the feasibility of germanium detector array deployment in a liquid neon environment to extend the physics reach of LEGEND; and develop preliminary designs and background models for the LEGEND-200 (200-kg) and LEGEND-1000 (1000-kg) phases of the LEGEND experiment.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.

中微子的非零质量和中性电荷使得中微子有可能是它们自己的反粒子（即马约拉纳粒子），在这种情况下，可能会发生一种极其罕见的核衰变形式，称为无中微子双β衰变（NLDBD） 。 如果中微子被证明是马约拉纳粒子，它将为中微子的质量非常小提供一个解释。指出新物理学的能量超出了我们最强大的对撞机的范围；并激发对宇宙中物质相对反物质普遍存在的解释。 该奖项支持测试中微子马约拉纳特性的实验和下一阶段实验（称为“LEGEND”）的软件和仪器研究。 这两个实验都使用超纯锗探测器，处于科学的前沿。 PI 将培训研究生新技术，使他们能够在高科技职业中竞争。 此外，PI 还制定了一项面向公众的创新计划。 LEGEND 实验将使用 MAJORANA Collaboration 开发的超纯材料和 GERDA Collaboration 开发的液态冷冻剂主动屏蔽来构建分阶段部署的吨级实验，该实验具有发现半衰期超过 10e28 年的 NLDBD 的潜力。 该项目将通过充分了解 MAJORANA DEMONSTRATOR 的背景并减少与液态制冷剂康普顿否决中的宇宙源氩同位素相关的背景，来扩展 LEGEND 对 NLDBD 和暗物质的敏感性。 具体而言，PI 及其团队的目标是： 使用蒙特卡罗模拟和实验数据构建 MAJORANA DEMONSTRATOR NLDBD 实验的综合背景模型；研究在液态氖环境中部署锗探测器阵列的可行性，以扩展 LEGEND 的物理范围；并为 LEGEND 实验的 LEGEND-200（200 公斤）和 LEGEND-1000（1000 公斤）阶段开发初步设计和背景模型。该奖项反映了 NSF 的法定使命，并通过使用基金会的评估进行评估，认为值得支持。智力价值和更广泛的影响审查标准。

项目成果

Search for neutrinoless double- β decay in Ge76 with 26 kg yr of exposure from the Majorana Demonstrator

在马约拉纳演示器每年暴露 26 公斤的情况下，寻找 Ge76 中的无中微子双β衰变

• DOI: 10.1103/physrevc.100.025501
• 发表时间: 2019-08
• 期刊: Physical Review C
• 影响因子: 3.1
• 作者: Alvis, S. I.;Arnquist, I. J.;Avignone, F. T.;Barabash, A. S.;Barton, C. J.;Basu, V.;Bertrand, F. E.;Bos, B.;Busch, M.;Buuck, M.;et al
• 通讯作者: et al

Multisite event discrimination for the majorana demonstrator

马约拉纳示威者的多站点事件歧视

• DOI: 10.1103/physrevc.99.065501
• 发表时间: 2019-06
• 期刊: Physical Review C
• 影响因子: 3.1
• 作者: Alvis, S. I.;Arnquist, I. J.;Avignone, F. T.;Barabash, A. S.;Barton, C. J.;Basu, V.;Bertrand, F. E.;Bos, B.;Buuck, M.;Caldwell, T. S.;et al
• 通讯作者: et al

ADC Nonlinearity Correction for the Majorana Demonstrator

马约拉纳演示器的 ADC 非线性校正

• DOI: 10.1109/tns.2020.3043671
• 发表时间: 2021-03
• 期刊: IEEE Transactions on Nuclear Science
• 影响因子: 1.8
• 作者: Abgrall, N.;Allmond, J. M.;Arnquist, I. J.;Avignone, F. T.;Barabash, A. S.;Barton, C. J.;Bertrand, F. E.;Bos, B.;Busch, M.;Buuck, M.;et al
• 通讯作者: et al

Search for Solar Axions via Axion-Photon Coupling with the Majorana Demonstrator

使用马约拉纳演示器通过轴子-光子耦合搜索太阳轴子

• DOI: 10.1103/physrevlett.129.081803
• 发表时间: 2022-08
• 期刊: Physical Review Letters
• 影响因子: 8.6
• 作者: Arnquist, I. J.;Avignone, F. T.;Barabash, A. S.;Barton, C. J.;Bhimani, K. H.;Blalock, E.;Bos, B.;Busch, M.;Buuck, M.;Caldwell, T. S.;et al
• 通讯作者: et al

Experimental study of C13(α,n)O16 reactions in the Majorana Demonstrator calibration data

马约拉纳演示器校准数据中 C13(α,n)O16 反应的实验研究

• DOI: 10.1103/physrevc.105.064610
• 发表时间: 2022-06
• 期刊: Physical Review C
• 影响因子: 3.1
• 作者: Arnquist, I. J.;Avignone, F. T.;Barabash, A. S.;Barton, C. J.;Bhimani, K. H.;Blalock, E.;Bos, B.;Busch, M.;Buuck, M.;Caldwell, T. S.;et al
• 通讯作者: et al