Microwave Imaging Spectropolarimetry of the Sun and Solar Activity

扩展欧文斯谷太阳能阵列（EOVSA）是一个专门研究太阳的无线电干涉仪，位于欧文斯谷射电天文台（OVRO）。它在微波频段收集太阳和空间天气现象的微波成像光谱偏振测量。提议者寻求将EOVSA作为社区资源运营，在收集后数小时内向所有用户公开数据。该阵列的主要科学目标是研究太阳耀斑、太阳活动区的磁场和等离子体结构，以及空间天气的驱动因素。EOVSA为频率敏捷太阳射电望远镜（FASR）提供了天线原型、馈电、模拟和数字系统、校准方法和数据管理的测试平台，FASR是提议的下一代太阳射电天文台。提议者将运行扩展欧文斯谷太阳能阵列，该阵列使用无线电干涉测量法在1-18 GHz频率范围内的一系列波段内每秒收集太阳的全圆盘图像，不包括1.9-2.4 GHz的噪声。瞬时带宽为500mhz；它在20毫秒内在每个频段之间切换，允许在1秒内完全覆盖整个频率范围。他们收集的数据将用于研究太阳耀斑、太阳活动区和空间天气的来源。EOVSA由13个2.1米的无线电天线组成，其中一个27米的天线用于高灵敏度校准。该阵列的面积为1.1公里乘1.2公里，每周7天，从日出到日落。提议者寻求将阵列用作社区仪器，不仅使数据可用于更大的太阳天文学和空间气象社区，而且还使用该系统作为原型系统的试验台，用于潜在的未来微波仪器。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。

The Expanded Owens Valley Solar Array (EOVSA) is a radio interferometer dedicated to the study of the Sun located at the Owens Valley Radio Observatory (OVRO). It collects microwave imaging spectropolarimetry measurements of the Sun and space weather phenomena in the microwave frequency band. The proposers seek to operate EOVSA as a community resource, making the data public to all users within hours of collection. The chief science aims of the array are the study of solar flares, the magnetic and plasma structure of solar active regions, and drivers of space weather. EOVSA provides a test bed for prototyping of antennas, feeds, analog and digital systems, calibration methods, and data management for the Frequency Agile Solar Radio Telescope (FASR), a proposed next-generation solar radio observatory.The proposers will operate the Expanded Owens Valley Solar Array, which uses radio interferometry to collect full-disk images of the Sun every second in a series of wavebands in the frequency range of 1-18 GHz, excluding 1.9-2.4 GHz due to noise. The instantaneous bandwidth is 500 MHz; it switches between each band in 20 ms, allowing full coverage of the whole frequency range in 1 second. The data they collect will be used to study solar flares, solar active regions, and sources for space weather. EOVSA consists of 13 2.1-meter radio dishes, with a 27-m dish used for high-sensitivity calibration. The array covers an area 1.1 by 1.2 kilometers in extent, and operates seven days a week, from sunrise to sunset. The proposers seek to use the Array as a community instrument, not only making the data available to the larger solar astronomy and space weather community, but also using the system a testbed for prototyping systems for potential future instrumentation in the microwave.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.