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Related papers: Will point sources spoil 21 cm tomography?

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The success of HI intensity mapping is largely dependent on how well 21cm foreground contamination can be controlled. In order to progress our understanding further, we present a range of simulated foreground data from four different…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-25 Steven Cunnington , Melis O. Irfan , Isabella P. Carucci , Alkistis Pourtsidou , Jérôme Bobin

21 cm tomography is expected to be difficult in part because of serious foreground contamination. Previous studies have found that line-of-sight approaches are capable of cleaning foregrounds to an acceptable level on large spatial scales,…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-05 Adrian Liu , Max Tegmark , Judd Bowman , Jacqueline Hewitt , Matias Zaldarriaga

In order to study the "Cosmic Dawn" and the Epoch of Reionization with 21 cm tomography, we need to statistically separate the cosmological signal from foregrounds known to be orders of magnitude brighter. Over the last few years, we have…

Tomography of redshifted 21 cm transition from neutral Hydrogen using Fourier synthesis telescopes is a promising tool to study the Epoch of Reionization (EoR). Limiting the confusion from Galactic and Extragalactic foregrounds is critical…

Instrumentation and Methods for Astrophysics · Physics 2015-05-28 Harish Vedantham , N. Udaya Shankar , Ravi Subrahmanyan

One of the main challenges for future 21 cm observations is to remove foregrounds which are several orders of magnitude more intense than the HI signal. We propose a new technique for removing foregrounds of the redshifted 21 cm…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Jungyeon Cho , A. Lazarian , P. Timbie

Current and upcoming 21-cm experiments will soon be able to map 21-cm spatial fluctuations in three dimensions for a wide range of redshifts. However, bright foreground contamination and the nature of radio interferometry create significant…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-01 Shu-Fan Chen , Kai-Feng Chen , Cora Dvorkin

One of the main challenges facing upcoming CMB experiments will be to distinguish the cosmological signal from foreground contamination. We present a comprehensive treatment of this problem and study how foregrounds degrade the accuracy…

Astrophysics · Physics 2009-10-07 Max Tegmark , Daniel J. Eisenstein , Wayne Hu , Angelica de Oliveira-Costa

The future of precision cosmology could benefit from cross-correlations between intensity maps of unresolved neutral hydrogen (HI) and more conventional optical galaxy surveys. A major challenge that needs to be overcome is removing the…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-17 Steven Cunnington , Laura Wolz , Alkistis Pourtsidou , David Bacon

Absorption or emission against the cosmic microwave background radiation (CMB) may be observed in the redshifted 21cm line if the spin temperature of the neutral intergalactic medium prior to reionization differs from the CMB temperature.…

Astrophysics · Physics 2009-12-10 Tiziana Di Matteo , Rosalba Perna , Tom Abel , Martin J. Rees

Although interesting in themselves, extragalactic sources emitting in the microwave range (mainly radio-loud active galactic nuclei and dusty galaxies) are also considered a contaminant from the point of view of Cosmic Microwave Background…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-31 P. Diego-Palazuelos , P. Vielva , D. Herranz

High-redshift 21-cm observations will provide crucial insights into the physical processes of the Epoch of Reionization. Next-generation interferometers such as the Square Kilometer Array will have enough sensitivity to directly image the…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-27 Simon Gazagnes , Léon V. E. Koopmans , Michael H. F. Wilkinson

The low-frequency radio sky is dominated by the diffuse synchrotron emission of our Galaxy and extragalactic radio sources related to Active Galactic Nuclei and star-forming galaxies. This foreground emission is much brighter than the…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-30 Emma Chapman , Vibor Jelić

Statistical observations of the Epoch of Reionization using the 21 cm line of neutral hydrogen have the potential to revolutionize our understanding of structure formation and the first luminous objects. However, these observations are…

Astrophysics · Physics 2008-11-26 Miguel F. Morales , Judd D. Bowman , Jacqueline N. Hewitt

We study the impact of sky-based calibration errors from source mismodeling on 21\,cm power spectrum measurements with an interferometer and propose a method for suppressing their effects. While emission from faint sources that are not…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-26 Aaron Ewall-Wice , Joshua S. Dillon , Adrian Liu , Jacqueline Hewitt

Techniques to improve the data quality of interferometric radio observations are considered. Fundaments of fringe frequencies in the uv-plane are discussed and filters are used to attenuate radio-frequency interference (RFI) and off-axis…

Instrumentation and Methods for Astrophysics · Physics 2012-04-02 A. R. Offringa , A. G. de Bruyn , S. Zaroubi

The Zwicky Transient Facility is a time-domain optical survey that has substantially increased our ability to observe and construct massive catalogs of astronomical objects by use of its 47 square degree camera that can observe in multiple…

Instrumentation and Methods for Astrophysics · Physics 2022-01-21 Michael S. Medford , Peter Nugent , Danny Goldstein , Frank J. Masci , Igor Andreoni , Ron Beck , Michael W. Coughlin , Dmitry A. Duev , Ashish A. Mahabal , Reed L. Riddle

Weak gravitational lensing from large-scale structure enhances and reduces the fluxes from extragalactic point sources with an rms amplitude of order 15%. In cosmic microwave background (CMB) experiments, sources exceeding some flux…

Astrophysics · Physics 2015-06-24 Max Tegmark , Jens Villumsen

Potential evidence for primordial non-Gaussianity (PNG) is expected to lie in the largest scales mapped by cosmological surveys. Forthcoming 21cm intensity mapping experiments will aim to probe these scales by surveying neutral hydrogen…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-20 Steven Cunnington , Stefano Camera , Alkistis Pourtsidou

We describe how the high-redshift 21-cm background can be used to improve both our understanding of the fundamental cosmological parameters of our Universe and exotic processes originating in the dark sector. The 21-cm background emerging…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-30 Steven R. Furlanetto