Illuminating our Early Universe with HERA, the Hydrogen Epoch of Reionization Array

用 HERA 照亮我们的早期宇宙，再电离阵列的氢时代

• 批准号: 1636646
• 负责人: Aaron Parsons
• 金额: $ 950万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-15 至 2021-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1636646&HistoricalAwards=false
• 关键词: Illuminating; our; Early; Universe; HERA

The objective of this program is to build a large array of low frequency radio antennas to study neutral hydrogen emission emitted at a frequency of 1420 MHz. This emission originated during the "epoch of reionization," when the universe transitioned from being predominantly neutral gas to being highly ionized. HERA, the Hydrogen Epoch of Reionization Array, will consist of 240 14-m parabolic dishes operating at observing frequencies from 50 to 250 MHz at the South African Square Kilometer Array site. HERA will be sensitive to hydrogen at great distances, shifted downward in radio frequency by the expansion of the universe. Broader impacts of the work include training of undergraduate and graduate students, and increased participation of underrepresented minorities in STEM research. The program for underrepresented minorities has two elements: an annual 10-week summer research program involving undergraduates and graduate students from the US and South Africa working on HERA science, and a series of training workshops for high school teachers with the involvement of the undergraduates.The HERA project will attempt to make the first detection of the distribution of the neutral Intergalactic Medium (IGM) between redshifts z=6-12 at the end of the epoch of reionization, possibly extending to z=30 if the required sensitivity at a frequency of 50 MHz is achieved. This will enable the three dimensional power-spectrum of the 21cm hydrogen line from the primordial IGM to be established. Eventually HERA is expected to image the bubbles of ionized gas expanding out from newly formed galaxies and quasars.

该程序的目的是建立大量的低频无线电天线，以研究以1420 MHz的频率排放的中性氢发射。这种发射起源于“电离时代”，当时宇宙从主要中性气体转变为高度电离。 HERA是电源阵列的氢时代，将由240 140米的抛物线菜肴组成，在南非平方公里阵列的观察频率从50到250 MHz的观测频率组成。 HERA将对氢气很敏感，并通过宇宙的扩展在射频下向下移动。这项工作的更广泛的影响包括对本科生和研究生的培训，以及代表性少数群体参与STEM研究的培训。 该计划的人为少数群体的计划有两个要素：一年一度的为期10周的夏季研究计划，涉及本科生和来自美国和南非从事HERA科学工作的研究生和研究生，以及针对高中老师的一系列培训讲习班，在本科生中参与。HERA项目将尝试在Z = 6-fift the Medif the Medif the Medif the Medif（IIF）中（IG）（IIF）（IG）（IG）（IG）（IG）（IG）（IG），IG级别的中性级别（IGM中）如果达到50 MHz频率所需的灵敏度，则可能会延伸至Z = 30。这将使能够从原始IgM建立21厘米氢系的三维功率光谱。最终，赫拉有望想象从新形成的星系和类星体扩张的电离气体的气泡。

项目成果

Constraining Polarized Foregrounds for EoR Experiments. II. Polarization Leakage Simulations in the Avoidance Scheme

• DOI: 10.3847/1538-4357/aa8b73
• 发表时间: 2017-07
• 期刊: The Astrophysical Journal
• 作者: C. Nunhokee;G. Bernardi;S. Kohn;J. Aguirre;N. Thyagarajan;J. Dillon;G. Foster;T. Grobler;J. Z. E. Martinot;A. Parsons

Understanding the HERA Phase I receiver system with simulations and its impact on the detectability of the EoR delay power spectrum

通过仿真了解 HERA 第一阶段接收器系统及其对 EoR 延迟功率谱可检测性的影响

• DOI: 10.1093/mnras/staa3268
• 发表时间: 2020
• 期刊: Monthly Notices of the Royal Astronomical Society
• 影响因子: 4.8
• 作者: Fagnoni, Nicolas;de Lera Acedo, Eloy;DeBoer, David R;Abdurashidova, Zara;Aguirre, James E;Alexander, Paul;Ali, Zaki S;Balfour, Yanga;Beardsley, Adam P;Bernardi, Gianni
• 通讯作者: Bernardi, Gianni

Optimizing sparse RFI prediction using deep learning

• DOI: 10.1093/mnras/stz1865
• 发表时间: 2019-02
• 期刊: Monthly Notices of the Royal Astronomical Society
• 影响因子: 4.8
• 作者: Joshua Kerrigan;P. Plante;S. Kohn;J. Pober;J. Aguirre;Zara Abdurashidova;P. Alexander;Z. Ali

Redundant interferometric calibration as a complex optimization problem

• DOI: 10.1093/mnras/sty357
• 发表时间: 2018-01
• 期刊: Monthly Notices of the Royal Astronomical Society
• 影响因子: 4.8
• 作者: T. Grobler;T. Grobler;G. Bernardi;G. Bernardi;J. Kenyon;A. Parsons;O. Smirnov

Unlocking Sensitivity for Visibility-based Estimators of the 21 cm Reionization Power Spectrum

• DOI: 10.3847/1538-4357/aaa029
• 发表时间: 2017-07
• 期刊: The Astrophysical Journal
• 作者: Y. Zhang;Adrian Liu;A. Parsons