English
Related papers

Related papers: Simulations for single-dish intensity mapping expe…

200 papers

Soon to be operational HI survey instruments such as APERTIF and ASKAP will produce large datasets. These surveys will provide information about the HI in and around hundreds of galaxies with a typical signal-to-noise ratio of $\sim$ 10 in…

Instrumentation and Methods for Astrophysics · Physics 2016-09-14 D. Punzo , J. M. van der Hulst , J. B. T. M. Roerdink

We present in this paper a new Bayesian semi-blind approach for foreground removal in observations of the 21-cm signal with interferometers. The technique, which we call HIEMICA (HI Expectation-Maximization Independent Component Analysis),…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-20 Le Zhang , Emory F. Bunn , Ata Karakci , Andrei Korotkov , P. M. Sutter , Peter T. Timbie , Gregory S. Tucker , Benjamin D. Wandelt

The 21-cm global signal is obscured by very bright galactic and extra galactic foreground emissions. Typical single-spectrum fit (SSF) based methods for foreground/signal separation can result in biased estimates of the cosmological signal…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-27 Yordan D. Ignatov , Jonathan R. Pritchard

The Planck survey has quantified polarized Galactic foregrounds and established that they are a main limiting factor in the quest for the cosmic microwave background (CMB) B-mode signal induced by primordial gravitational waves during…

The precise characterization and mitigation of systematic effects is one of the biggest roadblocks impeding the detection of the fluctuations of cosmological 21cm signals. Missing data in radio cosmological experiments, often due to radio…

Intensity mapping of neutral hydrogen (HI) is a promising observational probe of cosmology and large-scale structure. We present wide field simulations of HI intensity maps based on N-body simulations of a $2.6\, {\rm Gpc / h}$ box with…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-02 Sebastian Seehars , Aseem Paranjape , Amadeus Witzemann , Alexandre Refregier , Adam Amara , Joel Akeret

After reionization, neutral hydrogen (HI) traces the large-scale structure (LSS) of the Universe, enabling HI intensity mapping (IM) to capture the LSS in 3D and constrain key cosmological parameters. We present a new framework utilizing…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-10 Eishica Chand , Arka Banerjee , Simon Foreman , Francisco Villaescusa-Navarro

High fidelity separation of astrophysical foreground contributions from the cosmic microwave background (CMB) signal has been recognized as one of the main challenges of modern CMB data analysis, and one which needs to be addressed in a…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-19 Magdy Morshed , Arianna Rizzieri , Clément Leloup , Josquin Errard , Radek Stompor

The key challenge in the observation of the redshifted 21-cm signal from cosmic reionization is its separation from the much brighter foreground emission. Such separation relies on the different spectral properties of the two components,…

We present a new map-making method for CMB measurements. The method is based on the destriping technique, but it also utilizes information about the noise spectrum. The low-frequency component of the instrument noise stream is modelled as a…

Astrophysics · Physics 2009-11-10 E. Keihanen , H. Kurki-Suonio , T. Poutanen

Recent developments in the search for inflationary gravitational waves in the cosmic microwave background (CMB) polarization motivate the search for new diagnostics to distinguish the Galactic foreground contribution to B modes from the…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-11 Marc Kamionkowski , Ely D. Kovetz

The all-sky 408 MHz map of Haslam et al. is one the most important total-power radio surveys. It has been widely used to study diffuse synchrotron radiation from our Galaxy and as a template to remove foregrounds in cosmic microwave…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 M. Remazeilles , C. Dickinson , A. J. Banday , M. -A. Bigot-Sazy , T. Ghosh

Isotropy-violation statistics can highlight polarized galactic foregrounds that contaminate primordial $B$-modes in the Cosmic Microwave Background (CMB). We propose a particular isotropy-violation test and apply it to polarized Planck 353…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-23 Aditya Rotti , Kevin Huffenberger

Removing contaminants is a delicate, yet crucial step in neutral hydrogen (HI) intensity mapping and often considered the technique's greatest challenge. Here, we address this challenge by analysing HI intensity maps of about $100$ deg$^2$…

We study the impact of the 1/f noise on the PLANCK Low Frequency Instrument (LFI) osbervations (Mandolesi et al 1998) and describe a simple method for removing striping effects from the maps for a number of different scanning stategies. A…

Line intensity mapping (LIM) is an emerging observational method to study the large-scale structure of the Universe and its evolution. LIM does not resolve individual sources but probes the fluctuations of integrated line emissions. A…

Astrophysics of Galaxies · Physics 2020-06-03 Kana Moriwaki , Nina Filippova , Masato Shirasaki , Naoki Yoshida

The cosmic microwave background $B$-mode signal is potentially weaker than the diffuse Galactic foregrounds over most of the sky at any frequency. A common method of separating the CMB from these foregrounds is via pixel-based…

This paper provides full sky maps of foreground emission in all WMAP channels, with very low residual contamination from the Cosmic Microwave Background (CMB) anisotropies and controlled level of instrumental noise. Foreground maps are…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-25 Tuhin Ghosh , Jacques Delabrouille , Mathieu Remazeilles , Jean-Francois Cardoso , Tarun Souradeep

The cosmic infrared background (CIB) is a powerful probe of large-scale structure across a very large redshift range, and consists of unresolved redshifted infrared emission from dusty galaxies. It can be used to study the astrophysics of…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-02 Daniel Lenz , Olivier Doré , Guilaine Lagache

As Cosmic Microwave Background (CMB) measurements are becoming more ambitious, the issue of foreground contamination is becoming more pressing. This is especially true at the level of sensitivity, angular resolution and for the sky coverage…

Astrophysics · Physics 2009-10-31 François R. Bouchet , Richard Gispert