Collaborative Research: CEDAR: Measuring Daily Ionospheric Variability and the 2023 & 2024 Solar Eclipse Ionospheric Impacts Using HamSCI HF Doppler Shift Receivers

该项目将研究2023年和2024年发生的黎明/黄昏转换和两次日食所产生的整个美国大陆（CONUS）电离层变化。黎明和黄昏在观测到的电离层变率中产生复杂的响应，这一点至今仍未完全了解。一个名为Grapes的全球导航卫星系统（GNSS）稳定/同步高频（HF）接收器网络将用于该研究。30台Grape接收器将部署在北美各地，以优化对同时从两个地点接收到的电离层影响的研究。其他电台将由HamSCI业余无线电社区资助。该项目将产生观测结果，以回答以下科学问题：(1)黎明和黄昏电离层的变化如何随当地时间、季节、纬度、经度、频率、距离和与发射机的方向而变化？(2)日食电离层响应在开始和恢复时间上是否对称？(3)日食与每天黎明和黄昏的界限有多相似？(4)日食后的多径HF模式分裂是否与黎明事件相似？(5)两次日食的反应会不同吗？该项目是业余无线电科学公民调查（HamSCI）计划的一部分，将向想要现场仪器并为科学分析和讨论做出贡献的志愿者开放。该项目还将建立一个新的DASI仪器网络，由于其低成本和由志愿者操作，有可能在未来几年提供测量。本项目支持本科生、硕士和博士研究生。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This project will study ionospheric variability across the continental United States (CONUS) generated by dawn/dusk transitions and two solar eclipses occurring in 2023 and 2024. Dawn and dusk produce a complex response in observed ionospheric variability that is still not completely understood. A network of Global Navigation Satellite System (GNSS) stabilized/synchronized high frequency (HF) receivers known as Grapes will be used for the study. Thirty Grape receivers will be deployed throughout North America to optimize the study of the ionospheric impacts simultaneously received from two locations. Additional stations will be funded by the HamSCI amateur radio community. This project will generate observations to answer the scientific questions: (1) How do dawn and dusk ionospheric variability vary with local time, season, latitude, longitude, frequency, distance, and direction from the transmitter? (2) Is eclipse ionospheric response symmetric with regard to the onset and recovery timing? (3) How similar is the eclipse to the daily dawn and dusk terminator passage? (4) Would multipath HF mode-splitting in the post-eclipse interval be similar to dawn events? (5) Would the response be different for two eclipses?This project is part of the Ham Radio Science Citizen Investigation (HamSCI) program and will be open to volunteers who want to field instruments and contribute to scientific analysis and discussion. This project will also establish a new network of DASI instruments that, due to its low cost and operation by volunteers, has the potential to provide measurements for years to come. This project will support students (undergraduate, MS and Ph.D.).This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.