Precision field characterization for the next generation measurement of the neutron EDM

下一代中子 EDM 测量的精确场表征

• 批准号: 237136261
• 负责人: Professor Dr. Peter Fierlinger
• 金额: --
• 依托单位: Arbeitsgruppe Hadronenstruktur und Fundamentale Symmetrien
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2013
• 资助国家: 德国
• 起止时间: 2012-12-31 至 2017-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/237136261?language=en
• 关键词: Precision; field; characterization; next; generation

In this proposal we plan to realize a magnetic field measurement system for a next generation measurement of the neutron's electric dipole moment (EDM) with a sensitivity of 10-28 ecm. The system will be deployed for two purposes: (i) characterization of all kinds of fields from field coils and components inside the magnetically stabilized environment offline during installation and after of each component at their final location. This is in particular important for the EDM chamber parts, UCN optics and hardware inside the vacuum chamber. The figure of merit for the magnitude of contaminations is maximum 1 pT at 3 cm distance for inner components, giving rise to geometric phase effects. Goal (ii) is the measurement of magnetic fields during the EDM measurement online. Here, the long-term performance on a 100 fT level per sensor and the resolution of field direction on the 10-4 rad tilt-level is necessary. This helps to track changes of the shape of gradients from large and small localized sources using vector information while the experiment is operating. As all other in-situ (co-)magnetometers only provide averaged information, this is critical for the understanding of systematic effects. For this purpose we made tests with a fully optical Cs magnetometer system that is perfectly suitable for in-situ measurements online and offline without producing noise due to induced RF or magnetized hardware components. Within this project we would like to develop a set of such probes for both goals in 3 subsequent stages. Stage 1 is further optimization of sensors and their operation modes, stage 2 is the installation of a larger set of sensors on site for offline and online field mapping with commissioning and stage 3 is the operation, characterization and test against other systems.

在此提案中，我们计划实现一个磁场测量系统，用于对中子的电偶极矩（EDM）进行下一代测量，灵敏度为10-28 ECM。该系统将用于两个目的：（i）在安装过程中脱离磁性稳定环境内的磁场线圈和组件的各种字段的表征，并在其最终位置的每个组件之后。这对于真空室内的EDM室零件，UCN光学和硬件特别重要。污染幅度的优点为内部成分的最大1 pt在3 cm距离处，从而产生了几何相效应。目标（II）是在线EDM测量过程中磁场的测量。在这里，必须在每个传感器100英尺的水平上进行长期性能，以及在10-4 rad倾斜级别上的场方向的分辨率。这有助于在实验运行时使用向量信息从大小不一的局部源来跟踪梯度形状的变化。由于所有其他原位（共同）磁力仪仅提供平均信息，这对于理解系统效应至关重要。为此，我们使用完全光学CS磁力计系统进行了测试，该系统非常适合在线和离线的原位测量值，而不会因诱导的RF或磁化硬件组件而产生噪音。在这个项目中，我们想在随后的3个阶段中为两个目标开发一组此类探针。第1阶段是传感器的进一步优化及其操作模式，第2阶段是在现场安装较大的传感器以进行离线和在线域映射，并使用调试和第3阶段进行了对其他系统的操作，表征和测试。