Extracting 21 cm signal by frequency and angular filtering

doi:10.1088/1674-4527/18/9/114

CORC > 国家天文台 > 中国科学院国家天文台

	Extracting 21 cm signal by frequency and angular filtering
	Huang, Qi-Zhi 1,2,3,4; Wu, Feng-Quan 1; Ansari, Reza 3,4; Chen, Xuelei 1,2,5
刊名	RESEARCH IN ASTRONOMY AND ASTROPHYSICS
	2018-08-01
卷号	18 期号:9 页码:12
关键词	methods: data analysis (cosmology:) dark ages reionization, first stars cosmology: observations
ISSN号	1674-4527
DOI	10.1088/1674-4527/18/9/114
英文摘要	Extracting the neutral hydrogen (HI) signal is a great challenge for cosmological 21 cm experiments; both the astrophysical foregrounds and receiver noise are typically several orders of magnitude greater than the 21 cm signal. However, the different properties of the 21 cm signal, foreground and noise can be exploited to separate these components. The foregrounds are generally smooth or correlated over the frequency space along a line of sight (LoS), while both the 21 cm signal and noise vary stochastically along the same LoS. The foreground can be removed by filtering out the smooth component in frequency space. The receiver noise is basically uncorrelated for observations at different times, hence for surveys it is also uncorrelated in different directions, while the 21 cm signal, which traces the large scale structure, is correlated up to certain scales. In this exercise, we apply Wiener filters in frequency and angular space to extract the 21 cm signals. We found that the method works well. Inaccurate knowledge about the beam could degrade the reconstruction, but the overall result is still good, showing that the method is fairly robust.
资助项目	Ministry of Science and Technology[2016YFE0100300] ; National Natural Science Foundation of China[11473044] ; National Natural Science Foundation of China[U1501501] ; National Natural Science Foundation of China[U1631118] ; National Natural Science Foundation of China[11633004] ; Chinese Academy of Sciences[QYZDJ-SSW-SLH017] ; CSC Cai Yuanpei grant
WOS关键词	GALACTIC RADIO-EMISSION ; 1420 MHZ ; REIONIZATION ; EPOCH ; TOMOGRAPHY ; REDSHIFT ; MODEL ; MAPS ; SKY
WOS研究方向	Astronomy & Astrophysics
语种	英语
出版者	NATL ASTRONOMICAL OBSERVATORIES, CHIN ACAD SCIENCES
WOS记录号	WOS:000445688500010
资助机构	Ministry of Science and Technology ; Ministry of Science and Technology ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; Chinese Academy of Sciences ; Chinese Academy of Sciences ; CSC Cai Yuanpei grant ; CSC Cai Yuanpei grant ; Ministry of Science and Technology ; Ministry of Science and Technology ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; Chinese Academy of Sciences ; Chinese Academy of Sciences ; CSC Cai Yuanpei grant ; CSC Cai Yuanpei grant ; Ministry of Science and Technology ; Ministry of Science and Technology ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; Chinese Academy of Sciences ; Chinese Academy of Sciences ; CSC Cai Yuanpei grant ; CSC Cai Yuanpei grant ; Ministry of Science and Technology ; Ministry of Science and Technology ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; Chinese Academy of Sciences ; Chinese Academy of Sciences ; CSC Cai Yuanpei grant ; CSC Cai Yuanpei grant
内容类型	期刊论文
源URL	[http://ir.bao.ac.cn/handle/114a11/22731]
专题	中国科学院国家天文台
通讯作者	Chen, Xuelei
作者单位	1.Chinese Acad Sci, Key Lab Computat Astrophys, Natl Astron Observ, Beijing 100101, Peoples R China 2.Univ Chinese Acad Sci, Sch Astron & Space Sci, Beijing 100049, Peoples R China 3.Univ Paris Sud, LAL, UMR 8607, F-91898 Orsay, France 4.CNRS, IN2P3, F-91405 Orsay, France 5.Peking Univ, Ctr High Energy Phys, Beijing 100871, Peoples R China
推荐引用方式 GB/T 7714	Huang, Qi-Zhi,Wu, Feng-Quan,Ansari, Reza,et al. Extracting 21 cm signal by frequency and angular filtering[J]. RESEARCH IN ASTRONOMY AND ASTROPHYSICS,2018,18(9):12.
APA	Huang, Qi-Zhi,Wu, Feng-Quan,Ansari, Reza,&Chen, Xuelei.(2018).Extracting 21 cm signal by frequency and angular filtering.RESEARCH IN ASTRONOMY AND ASTROPHYSICS,18(9),12.
MLA	Huang, Qi-Zhi,et al."Extracting 21 cm signal by frequency and angular filtering".RESEARCH IN ASTRONOMY AND ASTROPHYSICS 18.9(2018):12.