657 citations · 2.5k across the 60 of their papers we have counts for
36 papers · 1 filter
Scalable Bayesian data curation for next-generation radio experiments
S. A. K. Leeney, E. de Lera Acedo, W. J. Handley +42
Next-generation radio telescopes produce data volumes that preclude manual quality assessment, yet data curation remains essential for science. We present a general, fully automati…
Optimisation of calibration sources for global 21-cm experiments: the REACH case
Adarsh Kumar Dash, Dominic Anstey, Harry T. J. Bevins +41
The spin-flip 21-cm signal from the Cosmic Dawn and the Epoch of Reionization is an essential probe of the conditions that led to the formation of the first luminous objects in the…
Circuit Modeling for In Situ 21 cm Radiometer Calibration
Gary Vincent Charles Allen, Saurabh Pegwal, Dirk de Villiers +42
Recent experiments in cosmology, particularly those aimed at detecting the faint, redshifted, global 21 cm hydrogen line (depth < ~200 mK, z > 7.5), have imposed stringent new requ…
Radiometer Calibration using Machine Learning
S. A. K. Leeney, H. T. J. Bevins, E. de Lera Acedo +35
Radiometers are crucial instruments in radio astronomy, forming the primary component of nearly all radio telescopes. They measure the intensity of electromagnetic radiation, conve…
The Bayesian Global Sky Model (B-GSM): A Calibrated Low Frequency Sky Model for EoR Applications
George Carter, Will Handley, Mark Ashdown +1
We present the Bayesian Global Sky Model (B-GSM), a new absolutely calibrated model of the diffuse Galactic foreground at frequencies below 408 MHz. We assemble a dataset of public…
The Bayesian Global Sky Model (B-GSM): Validation of a Data Driven Bayesian Simultaneous Component Separation and Calibration Algorithm for EoR Foreground Modelling
George Carter, Will Handley, Mark Ashdown +1
We introduce the Bayesian Global Sky Model (B-GSM), a novel data-driven Bayesian approach to modelling radio foregrounds at frequencies <400~MHz. B-GSM aims to address the limitati…
Mitigating calibration errors from mutual coupling with time-domain filtering of 21 cm cosmological radio observations
N. Charles, N. S. Kern, R. Pascua +80
The 21 cm transition from neutral Hydrogen promises to be the best observational probe of the Epoch of Reionisation (EoR). This has led to the construction of low-frequency radio i…
High-dimensional inference of radio interferometer beam patterns I: Parametric model of the HERA beams
Michael J. Wilensky, Jacob Burba, Philip Bull +6
Accurate modelling of the primary beam is an important but difficult task in radio astronomy. For high dynamic range problems such as 21cm intensity mapping, small modelling errors…
Hydrogen Epoch of Reionization Array (HERA) Phase II Deployment and Commissioning
Lindsay M. Berkhout, Daniel C. Jacobs, Zuhra Abdurashidova +93
This paper presents the design and deployment of the Hydrogen Epoch of Reionization Array (HERA) phase II system. HERA is designed as a staged experiment targeting 21 cm emission m…
matvis: A matrix-based visibility simulator for fast forward modelling of many-element 21 cm arrays
Piyanat Kittiwisit, Steven G. Murray, Hugh Garsden +95
Detection of the faint 21 cm line emission from the Cosmic Dawn and Epoch of Reionisation will require not only exquisite control over instrumental calibration and systematics to a…
Bayesian estimation of cross-coupling and reflection systematics in 21cm array visibility data
Geoff G. Murphy, Philip Bull, Mario G. Santos +76
Observations with radio arrays that target the 21-cm signal originating from the early Universe suffer from a variety of systematic effects. An important class of these are reflect…
Direct Optimal Mapping Image Power Spectrum and its Window Functions
Zhilei Xu, Honggeun Kim, Jacqueline N. Hewitt +79
The key to detecting neutral hydrogen during the epoch of reionization (EoR) is to separate the cosmological signal from the dominating foreground radiation. We developed direct op…
Receiver design for the REACH global 21-cm signal experiment
Ian L. V. Roque, Nima Razavi-Ghods, Steven H. Carey +35
We detail the the REACH radiometric system designed to enable measurements of the 21-cm neutral hydrogen line. Included is the radiometer architecture and end-to-end system simulat…
Bayesian jackknife tests with a small number of subsets: Application to HERA 21cm power spectrum upper limits
Michael J. Wilensky, Fraser Kennedy, Philip Bull +2
We present a Bayesian jackknife test for assessing the probability that a data set contains biased subsets, and, if so, which of the subsets are likely to be biased. The test can b…
Characterization Of Inpaint Residuals In Interferometric Measurements of the Epoch Of Reionization
Michael Pagano, Jing Liu, Adrian Liu +75
Radio Frequency Interference (RFI) is one of the systematic challenges preventing 21cm interferometric instruments from detecting the Epoch of Reionization. To mitigate the effects…
The Aperture Array Verification System 1: System overview and early commissioning results
P. Benthem, R. Wayth, E. de Lera Acedo +51
The design and development process for the Square Kilometre Array (SKA) radio telescope, the Low Frequency Aperture Array component, was progressed during the SKA pre-construction…
Automated Detection of Antenna Malfunctions in Large-N Interferometers: A Case Study with the Hydrogen Epoch of Reionization Array
Dara Storer, Joshua S. Dillon, Daniel C. Jacobs +75
We present a framework for identifying and flagging malfunctioning antennas in large radio interferometers. We outline two distinct categories of metrics designed to detect outlier…
Radio antenna design for sky-averaged 21 cm cosmology experiments: the REACH case
J. Cumner, E. De Lera Acedo, D. I. L. de Villiers +35
Following the reported detection of an absorption profile associated with the 21~cm sky-averaged signal from the Cosmic Dawn by the EDGES experiment in 2018, a number of experiment…
Validation of the HERA Phase I Epoch of Reionization 21 cm Power Spectrum Software Pipeline
James E. Aguirre, Steven G. Murray, Robert Pascua +73
We describe the validation of the HERA Phase I software pipeline by a series of modular tests, building up to an end-to-end simulation. The philosophy of this approach is to valida…
A Real Time Processing System for Big Data in Astronomy: Applications to HERA
Paul La Plante, Peter K. G. Williams, Matthew Kolopanis +72
As current- and next-generation astronomical instruments come online, they will generate an unprecedented deluge of data. Analyzing these data in real time presents unique conceptu…
Methods of Error Estimation for Delay Power Spectra in Cosmology
Jianrong Tan, Adrian Liu, Nicholas S. Kern +71
Precise measurements of the 21 cm power spectrum are crucial for understanding the physical processes of hydrogen reionization. Currently, this probe is being pursued by low-freque…
Bayesian noise wave calibration for 21-cm global experiments
I. L. V. Roque, W. J. Handley, N. Razavi-Ghods
Detection of millikelvin-level signals from the 'Cosmic Dawn' requires an unprecedented level of sensitivity and systematic calibration. We report the theory behind a novel calibra…
Design of the New Wideband Vivaldi Feed for the HERA Radio-Telescope Phase II
Nicolas Fagnoni, Eloy de Lera Acedo, Nick Drought +5
This paper presents the design of a new dual-polarised Vivaldi feed for the Hydrogen Epoch of Reionization Array (HERA) radio-telescope. This wideband feed has been developed to re…
Measuring HERA's primary beam in-situ: methodology and first results
Chuneeta D. Nunhokee, Aaron R. Parsons, Nicholas S. Kern +64
The central challenge in 21~cm cosmology is isolating the cosmological signal from bright foregrounds. Many separation techniques rely on the accurate knowledge of the sky and the…