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允许中微子是其自己的反粒子（即Majorana颗粒），在这种情况下，可能会发生一种超稀有的核衰减形式，称为中性中心linoless double-beta衰减（NLDBD）。 如果证明中微子是主要颗粒，它将为非常小的中微子提供一个解释。指出新物理学的能量超出了我们最强大的山脉的影响力；并激励对宇宙中反物质胜过物质流行的解释。 该奖项支持对实验的软件和仪器研究，以测试中微子的主要特征和下一阶段实验，称为传奇。 这两个实验均使用超纯净的锗探测器，并且处于科学的最前沿。 PI将培训研究生的新颖技术，这将使他们能够从事基于高科技的职业。 此外，PI还有一个创新的计划，以向公众推广。 传奇实验将使用Majoragana协作开发的超纯净材料以及GERDA协作开发的液体低温屏蔽，用于构建一个分阶段的部署量量表实验，其发现可能在10E28年以上的半衰期中发现NLDBD的发现潜力。 该项目将通过对Majorana演示者的背景以及与液体冷冻康普顿否决的宇宙氩同位素相关的背景进行充分的了解，从而扩展传奇对NLDBD和暗物质的敏感性。 具体而言，PI及其小组的目的是：使用Monte Carlo模拟和实验数据构建Majorana示威者NLDBD实验的全面背景模型；调查在液体霓虹灯环境中部署锗探测器阵列的可行性，以扩展传说的物理范围；并为传奇实验的传奇200（200-KG）和Legend-1000（1000公斤）阶段开发了初步设计和背景模型。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子优点和更广泛影响的审查标准来通过评估来获得支持的。

项目成果

Investigation of ASIC-based signal readout electronics for LEGEND-1000

• DOI: 10.1088/1748-0221/15/09/p09022
• 发表时间: 2020-05
• 期刊: Journal of Instrumentation
• 影响因子: 1.3
• 作者: F. Edzards;S. Mertens;L. Bombelli;G. Zuzel;D. Fink;S. Schönert;D. Radford;M. Green;M. Laubenstein;A. Alborini;G. Othman;M. Willers

ADC Nonlinearity Correction for the Majorana Demonstrator

• DOI: 10.1109/tns.2020.3043671
• 发表时间: 2021-03-01
• 期刊: IEEE TRANSACTIONS ON NUCLEAR SCIENCE
• 影响因子: 1.8
• 作者: Abgrall, N.;Allmond, J. M.;Shanks, B.
• 通讯作者: Shanks, B.

Signatures of muonic activation in the Majorana Demonstrator

马约拉纳演示器中μ子激活的特征

• DOI: 10.1103/physrevc.105.014617
• 发表时间: 2022
• 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.;Bertrand, F. E.;Blalock, E.;Bos, B.;Busch, M.;Buuck, M.;Caldwell, T. S.
• 通讯作者: Caldwell, T. S.

Search for trinucleon decay in the MAJORANA DEMONSTRATOR

• DOI: 10.1103/physrevd.99.072004
• 发表时间: 2019-04-12
• 期刊: PHYSICAL REVIEW D
• 影响因子: 5
• 作者: Alvis, S. I.;Arnquist, I. J.;Zhu, B. X.
• 通讯作者: Zhu, B. X.

Multisite event discrimination for the MAJORANA DEMONSTRATOR

• DOI: 10.1103/physrevc.99.065501
• 发表时间: 2019-06-07
• 期刊: PHYSICAL REVIEW C
• 影响因子: 3.1
• 作者: Alvis, S., I;Arnquist, I. J.;Zhu, B. X.
• 通讯作者: Zhu, B. X.