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The non-Gaussian nature of the epoch of reionization (EoR) 21-cm signal has a significant impact on the error variance of its power spectrum $P({\bf \textit{k}})$. We have used a large ensemble of semi-numerical simulations and an…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-26 Rajesh Mondal , Somnath Bharadwaj , Suman Majumdar

The 21 cm line of neutral hydrogen is a promising probe of the Epoch of Reionization (EoR) but suffers from contamination by spectrally smooth foregrounds, which obscure the large-scale signal along the line of sight. We explore the…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-26 Wenzer Qin , Kai-Feng Chen , Katelin Schutz , Adrian Liu

We show that Gaussian process regression (GPR) can be used to infer the electromagnetic (EM) duct height within the marine atmospheric boundary layer (MABL) from sparsely sampled propagation factors within the context of bistatic radars. We…

Atmospheric and Oceanic Physics · Physics 2020-07-15 Hilarie Sit , Christopher J. Earls

Experiments designed to measure the redshifted 21~cm line from the Epoch of Reionization (EoR) are challenged by strong astrophysical foreground contamination, ionospheric distortions, complex instrumental response and other different types…

An important application of next-generation wide-field radio interferometers is making high dynamic range maps of radio emission. Traditional deconvolution methods like CLEAN can give poor recovery of diffuse structure, prompting the…

Instrumentation and Methods for Astrophysics · Physics 2024-10-23 Katrine A. Glasscock , Philip Bull , Jacob Burba , Hugh Garsden , Michael J. Wilensky

Detecting a signal from the Epoch of Reionisation (EoR) requires an exquisite understanding of galactic and extra-galactic foregrounds, low frequency radio instruments, instrumental calibration, and data analysis pipelines. In this work we…

Instrumentation and Methods for Astrophysics · Physics 2020-02-27 Ronniy C. Joseph , C. M. Trott , R. B. Wayth , A. Nasirudin

The overwhelming foreground causes severe contamination on the detection of 21-cm signal during the Epoch of Reionization (EoR). Among various foreground components, the Galactic free-free emission is less studied, so that its impact on the…

Astrophysics of Galaxies · Physics 2020-07-07 Xiaoli Lian , Haiguang Xu , Dongchao Zheng , Zhenghao Zhu , Dan Hu

The ability to subtract foreground contamination from low-frequency observations is crucial to reveal the underlying 21 cm signal. The traditional line-of-sight methods can deal with the removal of diffuse emission and unresolved point…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Xiao-Chun Mao

Measurements of the Epoch of Reionization (EoR) 21-cm signal hold the potential to constrain models of reionization. In this paper we consider a reionization model with three astrophysical parameters namely (1) the minimum halo mass which…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-18 Abinash Kumar Shaw , Somnath Bharadwaj , Rajesh Mondal

BayesEoR is a GPU-accelerated, MPI-compatible Python package for estimating the power spectrum of redshifted 21-cm emission from interferometric observations of the Epoch of Reionization (EoR). Utilizing a Bayesian framework, BayesEoR…

Instrumentation and Methods for Astrophysics · Physics 2025-01-23 Peter H. Sims , Jacob Burba , Jonathan C. Pober

We present a survey strategy to detect the neutral hydrogen (HI) power spectrum at $5<z<6$ using the SKA-Low radio telescope in presence of foregrounds and instrumental effects. We simulate observations of the inherently weak HI signal…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-27 Zhaoting Chen , Emma Chapman , Laura Wolz , Aishrila Mazumder

The first generation of redshifted 21 cm detection experiments, carried out with arrays like LOFAR, MWA and GMRT, will have a very low signal-to-noise ratio per resolution element (\sim 0.2). In addition, whereas the variance of the…

Cross-correlation between the redshifted 21 cm signal and Lyman-{\alpha} emitters (LAEs) is powerful tool to probe the Epoch of Reionization (EoR). Although the cross-power spectrum (PS) has an advantage of not correlating with foregrounds…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-25 S. Yoshiura , J. L. B. Line , K. Kubota , K. Hasegawa , K. Takahashi

Detecting redshifted 21cm emission from neutral hydrogen in the early Universe promises to give direct constraints on the epoch of reionization (EoR). It will, though, be very challenging to extract the cosmological signal (CS) from…

The redshifted 21 cm line of neutral hydrogen is a promising probe of the Epoch of Reionization (EoR). However, its detection requires a thorough understanding and control of the systematic errors. We study two systematic biases observed in…

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…

We explore error distributions in Epoch of Reionization 21-cm power spectrum estimators using a combination of mathematical analysis and numerical simulations. We provide closed form solutions for the error distributions of individual bins…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-20 Michael J. Wilensky , Jordan Brown , Bryna J. Hazelton

We quantify the effect of radio frequency interference (RFI) on measurements of the 21-cm power spectrum during the Epoch of Reionization (EoR). Specifically, we investigate how the frequency structure of RFI source emission generates…

Instrumentation and Methods for Astrophysics · Physics 2020-09-09 Michael J. Wilensky , Nichole Barry , Miguel F. Morales , Bryna J. Hazelton , Ruby Byrne

We present a statistical analysis of a variant of the periodogram method that forms power spectral density estimates by cross-correlating the discrete Fourier transforms of adjacent time windows. The proposed estimator is closely related to…

Statistics Theory · Mathematics 2026-03-24 Mark Magsino

This paper explores the potential for statistical epoch of reionization (EOR) measurements using wide field radio observations. New developments in low frequency radio instrumentation and signal processing allow very sensitive EOR…

Astrophysics · Physics 2009-11-10 Miguel F. Morales , Jacqueline Hewitt