CDS&E: A Bayesian Approach to Detecting the Cosmological 21 cm Epoch of Reionization Signal

宇宙黎明是第一批恒星和星系形成的时候，对宇宙黎明的观测具有极大的挑战性，但对于绘制这一关键时期结构的分布和演化至关重要。这个项目将开发一种新的技术来研究这些第一个发光物体的性质。从数据中提取信息需要对系统误差的精确控制和对不确定性的详细核算。宇宙黎明和相关的再电离时代(EOR)是宇宙历史上的关键转折点，当时星系间氢被来自第一个光源处的高能光子重新电离。与现有的分析相比，这项工作将更清楚地区分真实信号和系统误差，并应在灵敏度方面提供数量级的改进，并相应地改善对当时发生的天体物理学的限制。该奖项将支持开发互动的、公开可用的在线教学资源，以培训21厘米宇宙学的新学生。这些资源将包括五至六个短片讲座，内容涉及无线电干涉计量学和21厘米宇宙学的关键入门专题。每一个视频将伴随着一次互动练习，使用由PI开发的在线软件。该奖项还将支持布朗大学非传统本科生研究经验(RETU)计划的继续，该计划为非传统学生提供深入的研究经验，包括第一代大学生、退伍军人和其他恢复教育的本科生，与他们密切合作，逐一进行。计划的方法依赖于对宇宙距离上微弱的21厘米中性氢线的观测。这项工作将在贝叶斯分析管道中纳入关键的新能力，并达到最大化科学回报所需的严格水平。这项分析将应用于再电离阵列的氢纪元(HERA)和Murchison Widefield阵列(MWA)的数据，以对21厘米的信号产生严格的新限制，并对宇宙黎明的物理学产生新的限制。这对于理解从宇宙微波背景揭示的简单、同质的早期宇宙向充满星系、恒星和行星的当前宇宙的过渡尤为重要。这一奖项反映了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。

Observations of the cosmic dawn, when the first stars and galaxies formed, are exceedingly challenging, but essential to map the distribution and evolution of structures during this critical period. This project will develop a new technique for studying the properties of these first luminous objects. Extracting information from the data requires precision control of systematic errors and detailed accounting of uncertainties. Cosmic dawn and the associated Epoch of Reionization (EoR), when intergalactic hydrogen was re-ionized by energetic photons from the first luminous sources, are critical turning points in the universe's history. Compared to existing analyses, this work will more clearly distinguish real signals from systematic errors, and should provide an order of magnitude improvement in sensitivity and correspondingly improved constraints on the astrophysics occurring at that time.This award will support the development of interactive, publicly available, online pedagogical resources for training new students in 21 cm cosmology. The resources will consist of five to six short video lectures covering key introductory topics in radio interferometry and 21 cm cosmology. Each video will be accompanied by an interactive exercise using online software developed by the PI. This award will also support the continuation of the Research Experiences for Non-Traditional Undergraduates (RENTU) program at Brown University, which provides in-depth research experiences to non-traditional students, including first-generation college students, veterans, and other resumed-education undergraduates, working closely with them on a case-by-case basis.The planned methods rely on observations of the faint 21 cm line of neutral hydrogen at cosmic distances. This work will incorporate critical new capabilities in a Bayesian analysis pipeline with the level of rigor needed to maximize the scientific returns. The analysis will be applied to data from the Hydrogen Epoch of Reionization Array (HERA) and the Murchison Widefield Array (MWA) to produce stringent new limits on the 21 cm signal and yield new constraints on the physics of the cosmic dawn. This is particularly important for understanding the transition from the simple, homogenous early universe revealed by the cosmic microwave background, to the current universe, filled with galaxies, stars, and planets.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.