Omnidirectional magnetometer in Brazil for dark matter search within GNOME

巴西的全向磁力计用于 GNOME 内的暗物质搜索

• 批准号: 439720477
• 负责人: Dr. Theo Scholtes
• 金额: --
• 依托单位: Leibniz-Institut für Photonische Technologien (IPHT)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2020
• 资助国家: 德国
• 起止时间: 2019-12-31 至 2023-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/439720477?language=en
• 关键词: Omnidirectional; magnetometer; Brazil; dark; matter

The Global Network of Optical Magnetometers for Exotic physics searches (GNOME) is an international collaboration hunting for signatures of dark matter (e.g., macroscopic structures formed by axions or axion-like particles) by looking for spin couplings in optically pumped magnetometers (OPM). Since in a single magnetometer it is not possible to discriminate an exotic interaction from the effect of a local magnetic field fluctuation, GNOME builds on detecting spatio-temporal correlations from an array of sensors, distributed around the globe. In its current state, the network consists of 12 active “stations”, i.e., sophisticated, magnetically well-shielded OPM setups, continuously streaming data to the collaboration server. From the analysis of first multi-station long-term runs limitations in the current-state network became apparent: All stations are located on the northern hemisphere. Moreover, all active magnetometers exhibit so-called “dead zones”, angular ranges in space, in which the sensors are blind for exotic (and magnetic) couplings. This leads to a reduced global and significantly less isotropic sensitivity in the Earth's coordinate system. Within this project, we propose to develop a new GNOME station to remedy these two limitations: Firstly, the station will be installed at the Vassouras geomagnetic observatory of the Observatorio Nacional, Brazil, making it the world's first station in the southern hemisphere. It will thus gain a strong weight in the reconstruction of the spatio-temporal course of exotic couplings. It will further improve the data quality of the network through advanced vetoing methods (to be developed and tested) using complementary sensor systems available on site (e.g. Vassouras is part of INTERMAGNET, the international network for observing the Earth's magnetic field). Secondly, we want to develop and investigate a novel OPM working scheme which is not only sensitive in a single direction, but in all three directions (omnidirectional) simultaneously, i.e. has no dead zones. We want to achieve this using an arrangement based on several miniaturized alkali vapor cells manufactured at Leibniz IPHT, which, by virtue of a new method, can be operated free of interfering crosstalk within a common magnetic shielding. Within the first phase of the project, a tried and tested OPM setup will be installed in Vassouras to ensure that data from the southern hemisphere will be available to the GNOME network in a timely manner. After the successful demonstration of the omnidirectional sensor in the laboratory, the Brazilian station will be upgraded to this scheme at the end of the project. All this together will allow GNOME to experimentally test classes of dark matter models with hitherto unprecedented sensitivity.

全球奇异物理搜索光磁力计网络（GNOME）是一个国际合作，通过寻找光泵浦磁力计（OPM）中的自旋耦合来寻找暗物质的特征（例如，由轴子或类轴子粒子形成的宏观结构）。由于在单个磁力计中不可能将外来相互作用与局部磁场波动的影响区分开来，因此GNOME建立在检测分布在全球各地的一系列传感器的时空相关性的基础上。在目前的状态下，该网络由12个活动“站”组成，即复杂的、具有良好磁性屏蔽的OPM设置，不断地向协作服务器传输数据。从首次多台站长期运行的分析可以看出，当前网络的局限性：所有台站都位于北半球。此外，所有有源磁强计都有所谓的“死区”，即空间的角度范围，在这个范围内，传感器对外来（和磁）耦合是看不到的。这导致了地球坐标系中全球和各向同性灵敏度的降低。在这个项目中，我们建议开发一个新的GNOME站来弥补这两个限制：首先，该站将安装在巴西国家天文台的瓦苏拉斯地磁观测站，使其成为世界上第一个在南半球的观测站。因此，它将在重建奇异耦合的时空过程中获得强大的权重。它将通过先进的否决方法（有待开发和测试）进一步提高网络的数据质量，使用现场可用的补充传感器系统（例如，Vassouras是INTERMAGNET的一部分，INTERMAGNET是观测地球磁场的国际网络）。其次，我们希望开发和研究一种新的OPM工作方案，该方案不仅在单一方向上敏感，而且在所有三个方向（全方向）同时敏感，即没有死区。我们希望利用莱布尼茨工业技术研究所（Leibniz IPHT）制造的几个小型化碱蒸汽电池的布置来实现这一目标，通过一种新的方法，它可以在一个共同的磁屏蔽内无干扰串扰地工作。在项目的第一阶段，将在Vassouras安装一个经过试验和测试的OPM设置，以确保来自南半球的数据将及时提供给GNOME网络。全向传感器在实验室演示成功后，巴西站将在项目结束时升级为该方案。所有这一切将使GNOME能够以迄今为止前所未有的灵敏度实验性地测试各种暗物质模型。