Coordination Funds

协调基金

• 批准号: 272268388
• 负责人: Professor Dr. Christian Walter Dietrich Enss
• 金额: --
• 依托单位: Arbeitsgruppe Fundamentale Teilchen und Wechselwirkungen
• 依托单位国家: 德国
• 项目类别: Research Units
• 财政年份: 2015
• 资助国家: 德国
• 起止时间: 2014-12-31 至 2023-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/272268388?language=en
• 关键词: Coordination; Funds

The determination of the absolute scale of the neutrino masses is one of the major challenges of today’s particle physics. Different approaches are fol-lowed to achieve a sensitivity on neutrino masses in the sub-eV range. Among them, experiments exploring the beta decay and electron capture processes of suitable nuclides can provide model-independent information on the electron (anti)- neutrino mass value purely using momentum and ener-gy conservation. The Electron Capture 163Ho experiment, ECHo, is aimed at investigating the electron neutrino mass in the sub-eV range by means of the analysis of the calorimetrically measured energy spectrum following the elec-tron capture process of 163Ho. In the ECHo experiment, arrays of low tem-per-ature metallic magnetic calorimeters with high energy resolution and fast response time, having the 163Ho source embedded in the absorber, will be used to calorimetrically measure the EC spectrum. Independent measure-ments of the decay energy (QEC-value), for which different experiments cur-rently provide values ranging from 2.3 to 2.8 keV, will be performed using Penning-trap mass spectrometry. For the QEC measurements as well as for the calorimetric measurement of the 163Ho spectrum, high purity 163Ho sources will be produced. Detailed studies of the background and of meth-ods for its reduction will be carried out to increase the sensitivity of the calo-rimetric measurement. Based on the preparatory work and the presently on-going R&D in the research groups of ECHo we propose to establish a DFG Re-search Unit with the goal to achieve the required experimental conditions and the knowledge to be able to investigate the electron neutrino mass in the sub-eV range and to foster the collaboration between the groups involved. Within the scope of this Research Unit, we propose to develop and construct a medium-size experiment featuring an activity of 1 kBq (ECHo-1k) with the aim of investigating the value of the electron neutrino mass in the range be-low 10 eV/c2 by means of a high-precision, high-statistics calorimetric measure-ment of the 163Ho EC spectrum. The expected result will improve the limit on the electron neutrino mass by more than one order of magnitude with respect to the presently most stringent limit of m(νe) < 225 eV/c2 (95% CL).

确定神经元肿块的绝对尺度是当今粒子物理学的主要挑战之一。遵循不同的方法，以达到对sub-eV范围内神经元肿块的敏感性。其中，实验探索了合适的核素的β衰变和电子捕获过程，可以提供有关电子（抗） - 神经元质量值的模型独立信息，纯粹是使用动量和能量守护的信息。电子捕获163HO实验ECHO旨在通过分析163ho的Elec-Tron捕获过程，通过分析Calolimetrimetremetrements测得的能量谱，研究子EV范围内的电子中性质量。在回声实验中，具有高能量分辨率和快速响应时间（将163HO源嵌入吸收剂中的163HO源）的临时金属磁caloliigeter的阵列将用于测量EC光谱。衰减能量（QEC值）的测量值当前提供了范围为2.3至2.8 keV的不同实验，将使用Penning-trap质谱法进行。对于QEC测量以及163HO频谱的Calolimetric测量，将产生高纯度163HO来源。对背景和MET-OD的还原的详细研究将进行减少，以提高Calo-Rimetric测量的灵敏度。根据编制工作以及目前正在进行的回声研究小组的研发，我们建议建立一个DFG研究单元，目的是达到所需的实验条件和知识，以便能够研究子-EV范围内的电子中性质量，并促进相关组之间的协作。在该研究单元的范围内，我们建议开发和构建一个中型实验，其活动的活动为1 kBQ（Echo-1K），目的是通过通过高级，高统计量化的量热测量测量值来研究电子神经元质量的价值。相对于当前最严格的M（νE）<225 eV/C2（95％Cl），预期的结果将提高电子神经元质量的极限。