200 citations · 1.6k across the 63 of their papers we have counts for
27 papers · 1 filter
Foreground Characterization and Mitigation in the Observations of the CD/EoR with the SKA
Philip Bull, Jacob Burba, Emilio Ceccotti +20
The Square Kilometre Array (SKA), with its unprecedented sensitivity, frequency coverage, and large collecting area, is poised to revolutionize our understanding of the Cosmic Dawn…
Overview of 21cm Experiments at high redshift with SKAO
CD Science Working Group, Gianni Bernardi, Daniela Breitman +81
We provide an overview of the eight SKAO Science Book chapters that motivate the Epoch of Reionisation and Cosmic Dawn experiments with SKA-Low. We describe the individual SKA-Low…
Exploring One-point Statistics in HERA Phase I Data: Effects of Foregrounds and Systematics on Measuring One-Point Statistics
Honggeun Kim, Jacqueline N. Hewitt, Nicholas S. Kern +61
Measuring one-point statistics in redshifted 21 cm intensity maps offers an opportunity to explore non-Gaussian features of the early universe. We assess the impact of instrumental…
Bayesian model comparison and validation with Gaussian Process Regression for interferometric 21-cm signal recovery
Yuchen Liu, Eloy de Lera Acedo, Peter Sims
The 21-cm signal from neutral hydrogen traces the formation and evolution of early cosmic structures during the Cosmic Dawn and the subsequent Epoch of Reionization. However, the i…
Can high-redshift AGN observed by JWST explain the EDGES absorption signal?
Alexandra Nelander, Christopher Cain, Jordan C J DSilva +3
The Experiment to Detect the Global Epoch of Reionization 21 cm Signal (EDGES) has reported evidence for an absorption feature in the sky-averaged radio background near 78 MHz. A c…
Rapid and Late Cosmic Reionization Driven by Massive Galaxies: a Joint Analysis of Constraints from 21-cm, Lyman Line & CMB Data Sets
Peter H. Sims, Harry T. J. Bevins, Anastasia Fialkov +6
Observations of the Epoch of Reionization (EoR) have the potential to answer long-standing questions of astrophysical interest regarding the nature of the first luminous sources an…
ECHO21: a tool for modelling global 21-cm signal from dark ages to reionization
Shikhar Mittal, Girish Kulkarni, Peter Sims
We introduce a Python package called ECHO21 for modelling the global 21-cm signal from the dark ages through cosmic dawn to the end of reionization. Leveraging its analytical frame…
A general Bayesian model-validation framework based on null-test evidence ratios, with an example application to global 21-cm cosmology
Peter H. Sims, Steven G. Murray, Judd D. Bowman +8
Comparing composite models for multi-component observational data is a prevalent scientific challenge. When fitting composite models, there exists the potential for systematics fro…
Impacts and Statistical Mitigation of Missing Data on the 21cm Power Spectrum: A Case Study with the Hydrogen Epoch of Reionization Array
Kai-Feng Chen, Michael J. Wilensky, Adrian Liu +66
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…
Investigating Mutual Coupling in the Hydrogen Epoch of Reionization Array and Mitigating its Effects on the 21-cm Power Spectrum
E. Rath, R. Pascua, A. T. Josaitis +78
Interferometric experiments designed to detect the highly redshifted 21-cm signal from neutral hydrogen are producing increasingly stringent constraints on the 21-cm power spectrum…
A demonstration of the effect of fringe-rate filtering in the Hydrogen Epoch of Reionization Array delay power spectrum pipeline
Hugh Garsden, Philip Bull, Mike Wilensky +94
Radio interferometers targeting the 21cm brightness temperature fluctuations at high redshift are subject to systematic effects that operate over a range of different timescales. T…
Search for the Epoch of Reionisation with HERA: Upper Limits on the Closure Phase Delay Power Spectrum
Pascal M. Keller, Bojan Nikolic, Nithyanandan Thyagarajan +80
Radio interferometers aiming to measure the power spectrum of the redshifted 21 cm line during the Epoch of Reionisation (EoR) need to achieve an unprecedented dynamic range to sep…
A Bayesian approach to modelling spectrometer data chromaticity corrected using beam factors -- I. Mathematical formalism
Peter H. Sims, Judd D. Bowman, Nivedita Mahesh +7
Accurately accounting for spectral structure in spectrometer data induced by instrumental chromaticity on scales relevant for detection of the 21-cm signal is among the most signif…
A General Bayesian Framework to Account for Foreground Map Errors in Global 21-cm Experiments
Michael Pagano, Peter Sims, Adrian Liu +3
Measurement of the global 21-cm signal during Cosmic Dawn (CD) and the Epoch of Reionization (EoR) is made difficult by bright foreground emission which is 2-5 orders of magnitude…
The REACH radiometer for detecting the 21-cm hydrogen signal from redshift 7.5 to 28
E. de Lera Acedo, D. I. L. de Villiers, N. Razavi-Ghods +31
Observations of the 21-cm line from primordial hydrogen promise to be one of the best tools to study the early epochs of the Universe: the Dark Ages, the Cosmic Dawn, and the subse…
Improved Constraints on the 21 cm EoR Power Spectrum and the X-Ray Heating of the IGM with HERA Phase I Observations
The HERA Collaboration, Zara Abdurashidova, Tyrone Adams +92
We report the most sensitive upper limits to date on the 21 cm epoch of reionization power spectrum using 94 nights of observing with Phase I of the Hydrogen Epoch of Reionization…
Impact of instrument and data characteristics in the interferometric reconstruction of the 21 cm power spectrum
Adélie Gorce, Samskruthi Ganjam, Adrian Liu +75
Combining the visibilities measured by an interferometer to form a cosmological power spectrum is a complicated process. In a delay-based analysis, the mapping between instrumental…
A Bayesian Calibration Framework for EDGES
Steven G. Murray, Judd D. Bowman, Peter H. Sims +5
We develop a Bayesian model that jointly constrains receiver calibration, foregrounds and cosmic 21cm signal for the EDGES global 21\,cm experiment. This model simultaneously descr…
Marginal Bayesian Statistics Using Masked Autoregressive Flows and Kernel Density Estimators with Examples in Cosmology
Harry Bevins, Will Handley, Pablo Lemos +3
Cosmological experiments often employ Bayesian workflows to derive constraints on cosmological and astrophysical parameters from their data. It has been shown that these constraint…
Direct Optimal Mapping for 21cm Cosmology: A Demonstration with the Hydrogen Epoch of Reionization Array
Zhilei Xu, Jacqueline N. Hewitt, Kai-Feng Chen +78
Motivated by the desire for wide-field images with well-defined statistical properties for 21cm cosmology, we implement an optimal mapping pipeline that computes a maximum likeliho…
First Results from HERA Phase I: Upper Limits on the Epoch of Reionization 21 cm Power Spectrum
The HERA Collaboration, Zara Abdurashidova, James E. Aguirre +74
We report upper-limits on the Epoch of Reionization (EoR) 21 cm power spectrum at redshifts 7.9 and 10.4 with 18 nights of data ( hours of integration) from Phase I of the…
HERA Phase I Limits on the Cosmic 21-cm Signal: Constraints on Astrophysics and Cosmology During the Epoch of Reionization
The HERA Collaboration, Zara Abdurashidova, James E. Aguirre +81
Recently, the Hydrogen Epoch of Reionization Array (HERA) collaboration has produced the experiment's first upper limits on the power spectrum of 21-cm fluctuations at z~8 and 10.…
Effects of model incompleteness on the drift-scan calibration of radio telescopes
Bharat K. Gehlot, Daniel C. Jacobs, Judd D. Bowman +76
Precision calibration poses challenges to experiments probing the redshifted 21-cm signal of neutral hydrogen from the Cosmic Dawn and Epoch of Reionization (z~30-6). In both inter…
Detection of Cosmic Structures using the Bispectrum Phase. II. First Results from Application to Cosmic Reionization Using the Hydrogen Epoch of Reionization Array
Nithyanandan Thyagarajan, Chris L. Carilli, Bojan Nikolic +69
Characterizing the epoch of reionization (EoR) at via the redshifted 21 cm line of neutral Hydrogen (HI) is critical to modern astrophysics and cosmology, and thus a k…