MRI: Development of the OVRO-LWA - A Low Frequency Radio Interferometric All-Sky Telescope

射电望远镜的概念通常会让人联想到巨大的碟子协调移动，凝视着天空的某一小部分。这个概念已经过时了--欧文斯山谷射电天文台-长波阵列(OVRO-LWA)将数百个小型廉价天线的信号结合在一起，瞬间成像整个天空，代表着革命性的新一代射电望远镜。由此产生的数据流是巨大的(每天12 PB)，但摩尔定律最终使连续处理和提取这些数据成为可能。通过全天候成像，OVRO-LWA可以同时实现许多关键的科学目标。它可以扫描附近数千个恒星系统，寻找系外行星磁层的无线电信号，这是行星宜居性的关键因素。它可以探测我们的宇宙黎明，这是我们宇宙的最早阶段，也就是第一批恒星形成的时候。它将在纳秒时间尺度上搜索天空，寻找最高能量宇宙射线的证据，并将提供对太阳(这与空间天气有关)和木星系统的持续监测。这一拟议的计划将使OVRO-LWA从概念验证发展为持续运行的设施，以及地球上最强大的射电望远镜在低无线电频率(100 MHz)下运行。天线的加入将把最大基线从1.5公里延长到2.6公里，并将使阵列的快照灵敏度提高3倍。望远镜接收电子设备将被新一代电子板取代，该电子板可以在704条信号路径(352个双极化天线)之间保持80分贝的隔离度，这是探测系外行星的弱极化信号以及隐藏在我们银河系明亮的污染射电发射中的宇宙黎明信号的基本要求。数字后端将是射电天文学有史以来最多功能的仪器，能够同时拍摄整个天空，形成12个高时间分辨率的波束，可以瞬间重定向到天空的任何方向，并从望远镜的原始数据中搜索持续几纳秒的宇宙射线射电阵雨。额外安装的4.4 PB存储系统将允许OVRO-LWA继续同时执行这些操作模式。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The concept of a radio telescope typically evokes imagery of giant dishes moving in unison, peering towards some small part of the sky. This notion is outdated - the Owens Valley Radio Observatory - Long Wavelength Array (OVRO-LWA) combines the signals from hundreds of small, cheap antennas to image the entire sky instantaneously, representing a revolutionary new generation of radio telescope. The resulting data stream is enormous (12 Petabytes per day), but Moore's Law has finally made it possible to continuously process and distill these data. By imaging all the sky, all the time, the OVRO-LWA can deliver a number of key science goals simultaneously. It can scan thousands of nearby stellar systems for the radio signature of exoplanet magnetospheres, a key ingredient for planetary habitability. It can probe our Cosmic Dawn, the earliest stages of our Universe when the very first stars formed. It will search the sky on nanosecond timescales for evidence of the highest energy cosmic rays, and it will provide continuous monitoring of the Sun (which is relevant for space weather), and Jovian system.This proposed program will progress the OVRO-LWA from a proof of concept to a continuously operational facility, and the most powerful radio telescope on the planet operating at low radio frequencies (100 MHz). The addition of 64 antennas will extend maximum baselines from 1.5 km to 2.6 km and will improve the snapshot sensitivity of the array by a factor of 3. The telescope receiver electronics will be replaced with a new generation of electronics board that can maintain 80 dB isolation between each of the 704 signal paths (352 dual polarization antennas), an essential requirement for detecting the weak polarized signatures of exoplanets as well as the Cosmic Dawn signal buried within the bright contaminating radio emission of our own Galaxy. The digital backend will be the most versatile instrument ever built for radio astronomy, being able to simultaneously image the entire sky, form 12 high time resolution beams that can be instantaneously repointed in any direction on the sky, and search the raw data from the telescope for cosmic ray radio showers lasting a few nanoseconds in duration. The additional installation of a 4.4 PB storage system will allow the OVRO-LWA to continuously execute these modes of operation simultaneously.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.