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Related papers: Hi intensity mapping with MeerKAT: Primary beam ef…

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Large Scale Structures (LSS) in the universe can be traced using the neutral atomic hydrogen HI through its 21cm emission. Such a 3D matter distribution map can be used to test the Cosmological model and to constrain the Dark Energy…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 R. Ansari , J. E. Campagne , P. Colom , J. M. Le Goff , C. Magneville , J. M. Martin , M. Moniez , J. Rich , C. Yèche

Twenty-one centimeter tomography is emerging as a powerful tool to explore the end of the cosmic dark ages and the reionization epoch, but it will only be as good as our ability to accurately model and remove astrophysical foreground…

Astrophysics · Physics 2008-11-26 Xiaomin Wang , Max Tegmark , Mario Santos , Lloyd Knox

Mapping the unresolved intensity of the 21-cm emission of neutral hydrogen (HI) is now regarded as one the most promising tools for cosmological investigation in the coming decades. Here, we investigate, for the first time, extensions of…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-05 Stefano Camera , Hamsa Padmanabhan

High-redshift protoclusters consisting of dusty starbursts are thought to play an important role in galaxy evolution. Their dusty nature makes them bright in the FIR/submm but difficult to find in optical/NIR surveys. Radio observations are…

We present a single-dish mapping algorithm with a number of advantages over traditional techniques. (1) Our algorithm makes use of weighted modeling, instead of weighted averaging, to interpolate between signal measurements. This smooths…

The cosmic microwave background (CMB) temperature bispectrum is currently the most precise tool for constraining primordial non-Gaussianity (NG). The Planck temperature data tightly constrain the amplitude of local-type NG: $f_{\rm NL}^{\rm…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-06 J. Colin Hill

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

Most deraining works focus on rain streaks removal but they cannot deal adequately with heavy rain images. In heavy rain, streaks are strongly visible, dense rain accumulation or rain veiling effect significantly washes out the image,…

Computer Vision and Pattern Recognition · Computer Science 2019-04-11 Ruotent Li , Loong Fah Cheong , Robby T. Tan

Pulsar Timing Arrays search for nanohertz-frequency gravitational waves by regularly observing ensembles of millisecond pulsars over many years to look for correlated timing residuals. Recently the first evidence for a stochastic…

Global 21cm cosmology aims to investigate the cosmic dawn and epoch of reionisation by measuring the sky averaged HI absorption signal, which requires, accurate modelling of, or correction for, the bright radio foregrounds and distortions…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-18 Dominic Anstey , Eloy de Lera Acedo , Will Handley

The removal of the Galactic and extragalactic foregrounds remains a major challenge for those wishing to make a detection of the Epoch of Reionization 21-cm signal. Multiple methods of modelling these foregrounds with varying levels of…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-13 Emma Chapman , Saleem Zaroubi , Filipe Abdalla , Fred Dulwich , Vibor Jelić , Benjamin Mort

Observations of the EoR with the 21-cm hyperfine emission of neutral hydrogen (HI) promise to open an entirely new window onto the formation of the first stars, galaxies and accreting black holes. In order to characterize the weak 21-cm…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-06 Abhik Ghosh , L. V. E. Koopmans , Emma Chapman , Vibor Jelic

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

We present an imaging technique that allows the recovery of the transparency profile of wavelength-scale objects with deep subwavelength resolution based on far-field intensity measurements. The approach, interscale mixing microscopy (IMM),…

Optics · Physics 2017-03-21 Sandeep Inampudi , Nicholas Kuhta , Viktor A. Podolskiy

Observation of multifrequency angular power spectrum of the redshifted 21-cm brightness temperature fluctuation from the neutral hydrogen holds the key to understand the structure formation and its evolution during the reionization and…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-28 Saikat Gayen , Jais Kumar , Prasun Dutta , Khandakar Md Asif Elahi , Samir Choudhuri , Nirupam Roy

The estimation of the polarization $P$ of extragalactic compact sources in Cosmic Microwave Background images is a very important task in order to clean these images for cosmological purposes -- as, for example, to constrain the…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-07 D. Herranz , F. Argüeso , L. Toffolatti , A. Manjón-García , M. López-Caniego

In 21cm intensity mapping of the large-scale structure (LSS), regions in Fourier space could be compromised by foreground contamination. In interferometric observations, this contamination, known as the foreground wedge, is exacerbated by…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-27 Qian Li , Xin Wang , Xiaodong Li , Jiacheng Ding , Tiancheng Luan , Xiaolin Luo

Radio astronomy is currently thriving with new large ground-based radio telescopes coming online in preparation for the upcoming Square Kilometre Array (SKA). Facilities like LOFAR, MeerKAT/SKA, ASKAP/SKA, and the future SKA-LOW bring…

Instrumentation and Methods for Astrophysics · Physics 2023-08-02 Benjamin Naoto Chiche , Julien N. Girard , Joana Frontera-Pons , Arnaud Woiselle , Jean-Luc Starck

We expect the monopole signal at the lowest frequencies below $100\,$MHz to be composed of two components: the deep Rayleigh-Jeans tail of the cosmic microwave background and two distinct features: the dark ages trough at $\sim 17\,$MHz and…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-04 Rugved Pund , Anže Slosar , Aaron Parsons

In the search for stochastic gravitational wave backgrounds (SGWB) of cosmological origin with LISA, it is crucial to account for realistic complications in the noise and astrophysical foreground modeling that may impact the signal…

General Relativity and Quantum Cosmology · Physics 2025-06-19 Jun'ya Kume , Marco Peloso , Mauro Pieroni , Angelo Ricciardone