Postdoctoral Fellowship: AAPF: Probing the Cosmic Dawn with the OVRO-LWA

Ruby Byrne被授予美国国家科学基金会天文学和天体物理学奖学金，在加州理工学院开展研究和教育项目。伯恩将利用中性氢的辐射来研究宇宙黎明，这是宇宙历史上恒星和星系最初形成的阶段。她还将领导一个面向高中生和本科生的暑期研究项目，让学生们接触天文数据分析技术，为他们从事科学事业做好准备。该项目采用了OVRO-LWA，这是一个位于加州欧文斯谷的无线电阵列，工作频率为12-85 MHz。升级后的OVRO-LWA第三阶段阵列对来自中性氢的21厘米发射线的高红移信号非常敏感，这些信号可以追踪宇宙黎明和再电离时期的星系间介质。Byrne将实施新的精确数据分析技术，以产生三个关键的科学结果：(1)测量天空平均21厘米频谱，(2)迄今为止对宇宙黎明期间21厘米波动的功率谱的最强约束，以及(3)低频无线电天空的高保保度极化图。这些结果将阐明早期星系形成的动力学，并检验宇宙演化的模型。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。

Ruby Byrne is awarded an NSF Astronomy and Astrophysics Fellowship to carry out a program of research and education at the California Institute of Technology. Byrne will use emission from neutral hydrogen to study the Cosmic Dawn, the phase in cosmological history when stars and galaxies first formed. She will also lead a summer research program for high school students and undergraduates that will expose students to astronomical data analysis techniques and prepare them for careers in science.This project employs the OVRO-LWA, a radio array in California’s Owens Valley that operates at frequencies of 12-85 MHz. The upgraded OVRO-LWA Stage III array is sensitive to highly redshifted signals from neutral hydrogen’s 21 cm emission line, which trace the intergalactic medium during the Cosmic Dawn and Epoch of Reionization. Byrne will implement novel precision data analysis techniques to produce three key science results: (1) a measurement of the sky-averaged 21 cm spectrum, (2) the strongest constraints to date on the power spectrum of 21 cm fluctuations during the Cosmic Dawn, and (3) high-fidelity, polarized maps of the low-frequency radio sky. These results will illuminate the dynamics of early galaxy formationmand test models of cosmological evolution.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.