利用双谱相位探测宇宙结构。II. 应用于宇宙再电离的初步结果——使用氢原子再电离纪元阵列
宇宙学与河外天体物理
2020-07-03 v2 天体物理仪器与方法
摘要
通过中性氢(HI)的红移 21 cm 谱线表征 的再电离纪元(EoR)对现代天体物理和宇宙学至关重要,因此是当前和计划中的许多低频射电望远镜的关键科学目标。探测该信号的主要挑战是在这些频率下压倒性明亮的前景辐射,对仪器知识和分析中的误差提出了严格要求。这些实验的结果主要受限的不是热灵敏度而是系统误差,特别是由于无法高精度定标仪器所致。干涉双谱相位不受基于天线的定标及其误差影响,并提供了一个独立的替代方案来探测 EoR HI 涨落,同时很大程度上避免定标系统误差。在此,我们展示了在氢原子再电离纪元阵列(HERA)的部分数据上应用该技术,以对星系际介质(IGM)亮温度给出近似约束。根据这一有限数据,在 时我们推断 IGM 亮温度的 "1\sigma" 上限为在 "pseudo" Mpc(数据受限)处 "pseudo" mK,以及在 "pseudo" Mpc(噪声受限)处 "pseudo" mK。"pseudo" 单位仅表示与实际距离尺度和亮温度的近似而非精确对应。通过将模型与数据分析并行传播,我们确认分离宇宙 HI 信号与前景所需的动态范围与标准方法相似,且双谱相位的功率谱仍是数据受限的(在 动态范围处),表明随着阵列建设的继续灵敏度有进一步改进的空间。
引用
@article{arxiv.2005.10275,
title = {Detection of Cosmic Structures using the Bispectrum Phase. II. First Results from Application to Cosmic Reionization Using the Hydrogen Epoch of Reionization Array},
author = {Nithyanandan Thyagarajan and Chris L. Carilli and Bojan Nikolic and James Kent and Andrei Mesinger and Nicholas S. Kern and Gianni Bernardi and Siyanda Matika and Zara Abdurashidova and James E. Aguirre and Paul Alexander and Zaki S. Ali and Yanga Balfour and Adam P. Beardsley and Tashalee S. Billings and Judd D. Bowman and Richard F. Bradley and Jacob Burba and Steve Carey and Carina Cheng and David R. DeBoer and Matt Dexter and Eloy de Lera Acedo and Joshua S. Dillon and John Ely and Aaron Ewall-Wice and Nicolas Fagnoni and Randall Fritz and Steven R. Furlanetto and Kingsley Gale-Sides and Brian Glendenning and Deepthi Gorthi and Bradley Greig and Jasper Grobbelaar and Ziyaad Halday and Bryna J. Hazelton and Jacqueline N. Hewitt and Jack Hickish and Daniel C. Jacobs and Austin Julius and Joshua Kerrigan and Piyanat Kittiwisit and Saul A. Kohn and Matthew Kolopanis and Adam Lanman and Paul La Plante and Telalo Lekalake and David Lewis and Adrian Liu and David MacMahon and Lourence Malan and Cresshim Malgas and Matthys Maree and Zachary E. Martinot and Eunice Matsetela and Mathakane Molewa and Miguel F. Morales and Tshegofalang Mosiane and Abraham R. Neben and Aaron R. Parsons and Nipanjana Patra and Samantha Pieterse and Jonathan C. Pober and Nima Razavi-Ghods and Jon Ringuette and James Robnett and Kathryn Rosie and Peter Sims and Craig Smith and Angelo Syce and Peter K. G. Williams and Haoxuan Zheng},
journal= {arXiv preprint arXiv:2005.10275},
year = {2020}
}
备注
22 pages, 12 figures (including sub-figures). Published in PhRvD. Abstract may be slightly abridged compared to the actual manuscript due to length limitations on arXiv