RII Track-4: Development of high-purity Ge detector technology with LBNL for dark matter and neutrino physics

我们对宇宙起源的理解和物质的基本性质是联系在一起的；然而，我们对这些学科的知识受到现有仪器和它们探测亚原子水平上发生的过程的能力的限制。该项目的目标是启动南达科他州大学（USD）和劳伦斯-伯克利国家实验室（LBNL）之间的长期合作，开发用于实验的新型探测器技术，旨在解决核物理学和宇宙学中一些最困难的问题，例如暗物质的真实性质，以及原子核如何结合在一起。拟议中的项目将为PI提供先进探测器开发方面的全面培训和经验，并将为他的职业发展建立必要的合作关系。拟议的项目也有可能在美元和有兴趣开发各种应用的辐射检测技术的公司之间建立伙伴关系，例如放射治疗和/或国土安全。鉴于开发这些先进探测器的能力增加，美元可能会刺激当地工业对辐射探测器的兴趣，从而促进当地经济发展。该合作研究有两个具体目标：(1)测量任意方向上的载流子漂移迁移率，以便更好地模拟高纯锗（HPGe）探测器中的电子信号形成；(2)研究在HPGe探测器中单独利用电离信号进行粒子识别的可能性。他们将通过两年的合作开发一系列平面HPGe探测器和具有低噪声前端电子器件的变温低温恒温器，由PI和他的研究生与LBNL的东道主科学家合作实现。合作过程中的知识转移将提高USD在HPGe探测器开发方面的能力，以及USD在基础物理研究方面的长期竞争力。对不同方向的迁移率的详细研究将有助于更好地理论理解和数值模拟HPGe探测器中电子信号形成过程，这对于中微子双β (0νββ)衰变实验中的信号/背景判别以及精确的&amp；#947；-核光谱学实验中的射线跟踪。最近，一个新的合作项目LEGEND成立了，它是两家基于最先进的HPGe的公司0&amp；#957;&#946；-衰变实验，GERDA和MJD，建立一个大型实验Ge中微子双β衰变搜索，使用HPGe探测器。东道国和东道国都加入了新的合作。他们的共同努力将帮助LEGEND从附属学术机构获得具有创新特性的HPGe探测器，以提高其灵敏度到0&amp；#957;β&#946；衰减的信号。

Non-technical DescriptionOur understanding of the origins of the universe and the fundamental nature of matter are linked; however, our knowledge of those subjects is limited by the available instruments and their abilities to detect processes that occur at subatomic levels. The goal of this project is to initiate a long-term collaboration between the University of South Dakota (USD) and the Lawrence-Berkeley National Laboratory (LBNL) to develop novel detector technologies for experiments that aim to solve some of the most difficult questions in nuclear physics and cosmology, such as the true nature of dark matter, and how atomic nuclei are bound together. The proposed project will provide the PI with comprehensive training and experience on advanced detector development, and will establish needed collaborations to further his career. The proposed project also has the potential to establish a partnership between USD and companies that are interested in developing radiation detection technologies for a variety of applications, such as radiation therapy and/or homeland security. Given the increased capacity to develop these advanced detectors, USD may stimulate the interest of local industry in radiation detectors, thereby contributing to local economic development.Technical DescriptionThis collaborative research has two specific objectives: (1) measuring charge carrier drift mobilities in arbitrary directions for better modeling of electronic signal formation in High Purity Germanium (HPGe) detectors; and (2) investigating the possibility of particle identification utilizing ionization signal alone in HPGe detectors. They will be achieved through two years of collaborative development of a series of planar HPGe detectors and a variable temperature cryostat with low-noise front-end electronics by the PI and his graduate student in partnership with the host scientist in LBNL. The knowledge transfer during the collaboration will improve both the HPGe detector development capacity at USD, and the long-term competitiveness of USD in fundamental physics research. Detailed study of mobilities in different directions will lead to better theoretic understanding and numerical modeling of electronic signal formation processes in HPGe detectors, which is essential for signal/background discrimination in neutrinoless double beta (0νββ) decay experiments and for precise γ-ray tracking in nuclear spectroscopy experiments. Recently, a new collaboration, LEGEND, was formed as a merged effort of two state-of-the-art HPGe based 0νββ-decay experiments, GERDA and MJD, to establish a Large Experiment for Ge Neutrinoless double beta Decay search, using HPGe detectors. Both the home and host institutes joined the new collaboration. Their joint effort will help LEGEND obtain HPGe detectors with innovative properties from affiliated academic institutions to improve their sensitivities to 0νββ-decay signals.