Collaborative Research: EDGES-3: Validating and Refining Global 21cm Measurements of Cosmic Dawn

合作研究：EDGES-3：验证和完善宇宙黎明的全球 21 厘米测量

• 批准号: 1909307
• 负责人: Colin Lonsdale
• 金额: $ 70.08万
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-08-01 至 2024-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1909307&HistoricalAwards=false
• 关键词: Collaborative; Research; EDGES; Validating; Refining

Astronomers are searching for signs of the first stars and galaxies that formed in the universe. This period in cosmic history is called the Epoch of Reionization (EoR). The Experiment to Detect the Global EoR Signature (EDGES) is an ongoing project to study this early period. In 2018, EDGES reported the first-ever detection of evidence of light from the first stars. These stars where shining 180 million years after the Big Bang, when the universe was merely one percent of its current age. The EDGES project uses radio observations to probe the early universe. This project will build a new radio antenna and receiver for EDGES. The instrument will be used to confirm previously reported evidence. Students from the diverse community of Arizona State University will help to build the instrument and analyze its data. This experience will help to prepare them for future careers and give them a unique research opportunity.Observing the formation of the first stars, galaxies, and black holes over 13.5 billion years ago is the next frontier in observational cosmology. After the first stars formed, they produced a background of ultra-violet photons that affected the surrounding hydrogen gas, enabling the gas to be detected in absorption against the cosmic microwave background. In early 2018 this research team reported the first evidence for detection of this signal, but the amplitude was twice the predicted level and the timing of the signal was earlier than expected. This project will develop a new radio antenna and receiver that will improve on previous performance by a factor of three, enabling a verification of the previous detection and detailed characterization of the signal. The project will engage students from Arizona State University to build the instrument and analyze its data, preparing them for future careers. The research team will disseminate technical advances in radio instrumentation through technical memos and journal articles.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.

天文学家正在寻找宇宙中形成的第一批恒星和星系的迹象。 宇宙历史上的这一时期被称为再电离时期（EoR）。探测全球EoR特征的实验（EDGES）是一个正在进行的研究这一早期阶段的项目。2018年，EDGES报告了有史以来第一次探测到来自第一批恒星的光的证据。这些恒星在宇宙大爆炸后的1.8亿年闪耀，当时宇宙只有现在年龄的百分之一。EDGES项目使用无线电观测来探测早期宇宙。该项目将为EDGES建立一个新的无线电天线和接收器。该仪器将用于确认先前报告的证据。来自亚利桑那州立大学多元化社区的学生将帮助建立仪器并分析其数据。这段经历将有助于他们为未来的职业生涯做好准备，并为他们提供一个独特的研究机会。观测135亿年前第一批恒星、星系和黑洞的形成是观测宇宙学的下一个前沿。在第一批恒星形成后，它们产生了影响周围氢气的紫外线光子背景，使这种气体能够在宇宙微波背景的吸收中被检测到。2018年初，该研究小组报告了检测到该信号的第一个证据，但幅度是预测水平的两倍，信号的时间比预期的要早。该项目将开发一种新的无线电天线和接收器，将以前的性能提高三倍，从而能够验证以前的检测和信号的详细特征。该项目将吸引亚利桑那州立大学的学生建造仪器并分析其数据，为他们未来的职业生涯做准备。该研究团队将通过技术备忘录和期刊文章传播无线电仪器的技术进步。该奖项反映了NSF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。

项目成果

Analytic Approximations of Scattering Effects on Beam Chromaticity in 21‐cm Global Experiments

21 cm 全局实验中散射对光束色度影响的解析近似

• DOI: 10.1029/2022rs007558
• 发表时间: 2022
• 期刊: Radio Science
• 影响因子: 1.6
• 作者: Rogers, Alan E.;Barrett, John P.;Bowman, Judd D.;Cappallo, Rigel;Lonsdale, Colin J.;Mahesh, Nivedita;Monsalve, Raul A.;Murray, Steven G.;Sims, Peter H.
• 通讯作者: Sims, Peter H.

Low-frequency Radio Recombination Lines Away from the Inner Galactic Plane

• DOI: 10.3847/1538-3881/ad08ba
• 发表时间: 2023-02
• 期刊: The Astronomical Journal
• 作者: Akshatha K. Vydula;J. Bowman;David Lewis;K. Crawford;M. Kolopanis;A. Rogers;S. Murray;N. Mahesh-N.

Absolute Calibration of Diffuse Radio Surveys at 45 and 150 MHz

45 和 150 MHz 漫射无线电测量的绝对校准

• DOI: 10.3847/1538-4357/abd558
• 发表时间: 2021
• 期刊: The Astrophysical Journal
• 作者: Monsalve, Raul A.;Rogers, Alan E.;Bowman, Judd D.;Mahesh, Nivedita;Murray, Steven G.;Mozdzen, Thomas J.;Johnson, Leroy;Barrett, John;Samson, Titu;Lewis, David
• 通讯作者: Lewis, David