Quantum Sensing of the Geomagnetic Space Weather Environment

1989年3月13日，上个世纪最大的磁暴对世界各地的电力系统造成了广泛影响，包括加拿大魁北克水电系统的停电。在93秒的时间里，它的电网崩溃，导致居民断电9个小时。在英国，两台大型电力变压器严重受损，需要昂贵的维修费用。在其间的30年里，社会变得更加依赖持续供电、全球导航卫星系统、宽带互联网、移动电话通信和其他服务，这些服务可能受到所谓的空间天气的严重影响，特别是磁场在几秒到几分钟量级上的快速变化所产生的影响。据预计，比当代英国3月风暴更严重的事件可能会造成每天数十亿英镑的经济损失。测量风暴期间地磁的变化具有重要的国家意义，有助于了解空间天气造成的危害。虽然目前在英国地磁观测站测量磁场的科学仪器(称为磁通门磁力计)非常灵敏，但它们不足以完成绝对快速、高精度和无噪音的磁场测量任务。我们希望建造和部署一种被称为光泵磁强计的新型传感器。它使用过去十年开发的尖端量子技术来测量玻璃电池内铯(Cs)原子的振动，这种振动能够检测到地球磁场的微小变化。作为一个额外的好处，新的磁力计降低了传感器的尺寸、重量和功率要求，同时与目前的仪器相比，其精度提高了100倍以上。为了测试新的光泵磁力计，我们将在苏格兰边境的Eskdalemuir地磁观测站与科学仪器并行运行六个月。这个地点自1904年以来一直有一个世界领先的天文台在运行，是英国最干净的磁性地点之一。一旦对性能进行了评估，还将建造另外五个OPM传感器，集成到定制的通信和电源中，并部署到英国各地的偏远地点，以增强BGS的空间天气监测网络。与现有的地磁仪器相结合，我们将实现拥有最密集的国家磁力仪网络的世界第一。这将超过世界气象组织(WMO)提出的磁力站之间距离不超过200公里的建议。该项目将结合斯特拉斯克莱德大学物理系制造传感器的技术技能，以及雷尔空间公司的电子系统经验，以优化其性能。英国地质调查局地磁团队在部署和运行长期设施以及验证磁性仪器的准确性方面拥有丰富的经验。这是一个跨学科的项目，有可能以一种新的高精度磁力仪的形式带来技术、科学、社会和经济效益，该磁力仪可以部署在英国(和世界各地)，以研究危险空间天气的影响。

On 13 March 1989, the largest magnetic storm of the last century caused widespread effects on power systems around the world including a blackout of the Hydro-Québec system in Canada. In the space of 93 seconds, its power grid collapsed leaving residents without electricity for 9 hours. In the UK, two large power transformers were severely damaged and required expensive repairs. In the intervening 30 years, society has become much more reliant on continuous power supply, global navigation satellite systems (GNSS), broadband internet, mobile phone communication and other services which can be badly affected by so-called space weather, specifically the effects generated by rapid variations of the magnetic field on the order of seconds to minutes. It is anticipated that a more severe event than the March 1989 storm in the contemporary UK could cause economic damage on the order of billions of pounds per day. Measuring changes of the geomagnetic during a storm is of critical national importance and can help understand the hazards posed from space weather. While present day scientific-level instruments that measure the magnetic field (called fluxgate magnetometers) at UK geomagnetic observatories are very sensitive, they are not quite sufficient for the task of making absolute rapid, high-accuracy and noise-free measurements of the magnetic field. We wish to build and deploy a new type of sensor known as an optically pumped magnetometer. This uses cutting-edge quantum technology, developed in the last decade, to measure the vibrations of Caesium (Cs) atoms inside a glass cell which are able to detect small changes of the Earth's magnetic field. As a bonus, the new magnetometers reduce the size, weight and power requirements of a sensor while increasing its accuracy over 100-fold compared to current instrumentation. To test the new optically pumped magnetometer we will run it in parallel with the scientific instruments at the Eskdalemuir geomagnetic observatory in the Scottish borders for six months. This location has had a world-leading observatory in operation since 1904 and is one of the magnetically cleanest sites in the UK. Once the performance has been assessed a further five OPM sensors will be built, integrated into a bespoke communications and power supply and deployed to remote sites across the UK to augment the BGS space weather monitoring network. In conjunction with the existing geomagnetic instruments, we will achieve a world first with the densest national network of magnetometers. This will surpass the World Meteorological Organisation (WMO) recommendation of no more than 200 km between magnetic stations.The project will bring together the technical skills of the University of Strathclyde's Physics Department to build the sensor, along with RAL Space's electronic system experience to optimise its performance. The British Geological Survey Geomagnetism team have ample experience in deploying and running long term installations and validating the accuracy of magnetic instruments. This is a cross-disciplinary project with the potential to bring technical, scientific, social and economic benefit in the form of a new high accuracy magnetometer than the can be deployed across the UK (and the world) in order to study the effects of hazardous space weather.