Erasing the Milky Way: new cleaning technique applied to GBT intensity mapping data

doi:10.1093/mnras/stw2556

	Erasing the Milky Way: new cleaning technique applied to GBT intensity mapping data
	Yadav, J.10; Voytek, T. C.6; Pen, U. -L.5; Wolz, L.8,9; Blake, C.7; Abdalla, F. B.11; Anderson, C. J.12; Chang, T. -C.13; Li, Y. -C.1; Masui, K. W.2,3
刊名	MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
	2017-02-01
卷号	464 期号:4 页码:4938-4949
关键词	Methods: Data Analysis Methods: Statistical Cosmology: Observations Large-scale Structure Of Universe Radio Lines: Galaxies
DOI	10.1093/mnras/stw2556
文献子类	Article
英文摘要	We present the first application of a new foreground removal pipeline to the current leading HI intensity mapping data set, obtained by the Green Bank Telescope (GBT). We study the 15- and 1-h-field data of the GBT observations previously presented in Mausui et al. and Switzer et al., covering about 41 deg(2) at 0.6 < z < 1.0, for which cross-correlations may be measured with the galaxy distribution of the WiggleZ Dark Energy Survey. In the presented pipeline, we subtract the Galactic foreground continuum and the point-source contamination using an independent component analysis technique (FASTICA), and develop a Fourier-based optimal estimator to compute the temperature power spectrum of the intensity maps and cross-correlation with the galaxy survey data. We show that FASTICA is a reliable tool to subtract diffuse and point-source emission through the non-Gaussian nature of their probability distributions. The temperature power spectra of the intensity maps are dominated by instrumental noise on small scales which FASTICA, as a conservative subtraction technique of non-Gaussian signals, cannot mitigate. However, we determine similar GBT-WiggleZ cross-correlation measurements to those obtained by the singular value decomposition (SVD) method, and confirm that foreground subtraction with FASTICA is robust against 21 cm signal loss, as seen by the converged amplitude of these cross-correlation measurements. We conclude that SVD and FASTICA are complementary methods to investigate the foregrounds and noise systematics present in intensity mapping data sets.
WOS关键词	DIGITAL SKY SURVEY ; INDEPENDENT COMPONENT ANALYSIS ; DARK ENERGY SURVEY ; ACOUSTIC-OSCILLATIONS ; POWER SPECTRUM ; 21-CM EMISSION ; DATA RELEASE ; TO 0.8 ; GALAXY ; MAPS
WOS研究方向	Astronomy & Astrophysics
语种	英语
WOS记录号	WOS:000393780500083
资助机构	Australian Research Council Centre of Excellence for All-sky Astrophysics (CAASTRO)(CE110001020) ; Australian Research Council Centre of Excellence for All-sky Astrophysics (CAASTRO)(CE110001020) ; Australian Research Council ; Australian Research Council ; Australian Research Council Centre of Excellence for All-sky Astrophysics (CAASTRO)(CE110001020) ; Australian Research Council Centre of Excellence for All-sky Astrophysics (CAASTRO)(CE110001020) ; Australian Research Council ; Australian Research Council
内容类型	期刊论文
源URL	[http://ir.bao.ac.cn/handle/114a11/8887]
专题	国家天文台_星系宇宙学研究部
作者单位	1.Chinese Acad Sci, Natl Astron Observ, 20A Datun Rd, Beijing 100012, Peoples R China 2.Univ British Columbia, Dept Phys & Astron, 6224 Agr Rd, Vancouver, BC V6T 1Z1, Canada 3.Canadian Inst Adv Res, CIFAR Program Cosmol & Grav, Toronto, ON M5G 1Z8, Canada 4.NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA 5.Canadian Inst Theoret Astrophys, 60 St George St, Toronto, ON M5S 3H8, Canada 6.Univ KwaZulu Natal, Sch Chem & Phys, Astrophys & Cosmol Res Unit, ZA-4041 Durban, South Africa 7.Swinburne Univ Technol, Ctr Astrophys & Supercomp, POB 218, Hawthorn, Vic 3122, Australia 8.Univ Sydney, Sch Phys, ARC Ctr Excellence All Sky Astrophys CAASTRO, Bldg A28, Sydney, NSW 2006, Australia 9.Univ Melbourne, Sch Phys, Parkville, Vic 3010, Australia 10.Univ Delhi, Sri Aurobindo Coll, New Delhi 110017, India
推荐引用方式 GB/T 7714	Yadav, J.,Voytek, T. C.,Pen, U. -L.,et al. Erasing the Milky Way: new cleaning technique applied to GBT intensity mapping data[J]. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY,2017,464(4):4938-4949.
APA	Yadav, J..,Voytek, T. C..,Pen, U. -L..,Wolz, L..,Blake, C..,...&Switzer, E..(2017).Erasing the Milky Way: new cleaning technique applied to GBT intensity mapping data.MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY,464(4),4938-4949.
MLA	Yadav, J.,et al."Erasing the Milky Way: new cleaning technique applied to GBT intensity mapping data".MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 464.4(2017):4938-4949.