Search for Neutrinoless Double Beta Decay with NEMO-3 and Super-NEMO Experiments

对中微子振荡的观测表明，中微子具有质量。这是超越标准模型的物理学的第一个直接证据。这一发现重新燃起了人们对无中微子双β衰变实验的兴趣，双β衰变实验提供了确定中微子是马约拉纳粒子还是狄拉克粒子的唯一实用方法。这样的实验也有可能确定中微子质量的绝对规模，并帮助解决中微子质量层次问题。这些基本问题的答案对于更好地理解自然的基本力量和宇宙的演化可能很重要。该提案的作者希望参与正在进行的实验NEMO-3，这是目前对中微子双β衰变最敏感的搜索，以及下一代实验Super-NEMO。NEMO团队目前正在操作NEMO-3设备，该设备位于法国-意大利阿尔卑斯山下Frejus隧道的Modane地下实验室。在Super-NEMO中，就像在NEMO-3中一样，不像在大多数其他的中微子双β衰变实验中，最终状态是通过几个与拓扑结构和电子能量相关的可观测值来重建的。这是粒子物理和核物理实验中常用的一种技术，为测量和抑制背景提供了有力的工具。该小组已被邀请加入NEMO合作，在NEMO-3和Super-NEMO上工作，并带来他们在闪烁体量热计方面的专业知识。他们正在开发一种基于GEANT-4的模拟包，该包将成为Super-NEMO的核心光学包，也是几个实验室研究Super-NEMO各种热量计选项的重要研发工具。他们都验证了模拟结果，并构建了原型，这可以为Super-NEMO的最终设计提供有价值的输入。这项提议的广泛影响源于这样一个事实，即超级尼莫本质上是许多小型子探测器的集合，可以在工作台上制作原型并操作。这非常适合培训和教育本科生。

The observation of neutrino oscillations has shown that neutrinos have mass. This is the first direct evidence of physics beyond the Standard Model. This discovery has renewed and strengthened interest in neutrinoless double beta decay experiments which provide the only practical way to determine whether neutrinos are Majorana or Dirac particles. Such experiments have also the potential to determine the absolute scale of the neutrino mass and help resolve the neutrino mass hierarchy question. The answers to these fundamental issues may be important to a better understanding of the fundamental forces of Nature and the evolution of the Universe. The authors of this proposal wish to participate in the ongoing experiment NEMO-3, currently the most sensitive search for neutrinoless double beta decays, and in the next generation experiment Super-NEMO. The NEMO team currently operates the NEMO-3 apparatus, located in the Modane Underground Laboratory in the Frejus Tunnel under the French-Italian Alps. In Super-NEMO, just as in NEMO-3, and unlike in most other neutrinoless double beta decay experiments, the final state is reconstructed through several observables relating topology and electron energy. This is a technique common to particle and nuclear physics experiments and provides a powerful tool for measuring and rejecting background. This group has been invited to join the NEMO collaboration to work on both NEMO-3 and Super-NEMO and to bring their expertise with scintillator calorimeters. They are developing a simulation package based on GEANT-4 which is becoming the core optics package for Super-NEMO and an important R&D tool in several labs investigating various calorimeter options for Super-NEMO. They have both validated the results of simulations and constructed prototypes which could provide a valuable input to the final design of Super-NEMO. The broader impact of this proposal stems from the fact that Super-NEMO is essentially an assembly of many small sub-detectors which can be prototyped and operated on a bench. This is ideally suited for training and educating undergraduate students.