The Impact of Beam Variations on Power Spectrum Estimation for 21-cm Cosmology I: Simulations of Foreground Contamination for HERA

Abstract

Detecting cosmological signals from the Epoch of Reionization (EoR) requires high-precision calibration to isolate the cosmological signals from foreground emission. In radio interferometery, perturbed primary beams of antenna elements can disrupt the precise calibration, which results in contaminating the foreground-free region, or the EoR window, in the cylindrically averaged power spectrum. For Hydrogen Epoch of Reionization Array (HERA), we simulate and characterize the perturbed primary beams induced by feed motions such as axial, lateral, and tilting motions, above the 14-meter dish. To understand the effect of the perturbed beams, visibility measurements are modeled with two different foreground components, point sources and diffuse sources, and we find different feed motions present a different reaction to each type of sky source. HERA's redundant-baseline calibration in the presence of non-redundant antenna beams due to feed motions introduces chromatic errors in gain solutions, which produces foreground power leakage into the EoR window. The observed leakage from vertical feed motions comes predominately from point sources around zenith. Furthermore, the observed leakage from horizontal and tilting feed motion comes predominately from the diffuse components near the horizon. Mitigation of chromatic gain errors will be necessary for robust detection of the EoR signals with minimal foreground bias, and this will be discussed in the subsequent paper.

arXiv commentAccepted for publication in ApJ

References in corpus (71)

• SciPy 1.0--Fundamental Algorithms for Scientific Computing in Python
• Planck 2015 results. XIII. Cosmological parameters
• HEALPix -- a Framework for High Resolution Discretization, and Fast Analysis of Data Distributed on the Sphere
• LOFAR: The LOw-Frequency ARray
• Cosmology at Low Frequencies: The 21 cm Transition and the High-Redshift Universe
• The Murchison Widefield Array: the Square Kilometre Array Precursor at low radio frequencies
• 21cmFAST: A Fast, Semi-Numerical Simulation of the High-Redshift 21-cm Signal
• Hydrogen Epoch of Reionization Array (HERA)
• GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey I: A low-frequency extragalactic catalogue
• The Precision Array for Probing the Epoch of Reionization: 8 Station Results
• Bright Source Subtraction Requirements For Redshifted 21 cm Measurements
• What Next-Generation 21 cm Power Spectrum Measurements Can Teach Us About the Epoch of Reionization
• The Evolution of the Intergalactic Medium
• A simulation calibrated limit on the HI power spectrum from the GMRT Epoch of Reionization experiment
• A Per-Baseline, Delay-Spectrum Technique for Accessing the 21cm Cosmic Reionization Signature
• Four Fundamental Foreground Power Spectrum Shapes for 21 cm Cosmology Observations
• Improved upper limits on the 21-cm signal power spectrum of neutral hydrogen at $\mathbf{z}\approx 9.1$ from LOFAR
• Upper limits on the 21-cm Epoch of Reionization power spectrum from one night with LOFAR
• New Limits on 21cm EoR From PAPER-32 Consistent with an X-Ray Heated IGM at z=7.7
• Data Analysis for Precision 21 cm Cosmology
• Imaging the Epoch of Reionization: limitations from foreground confusion and imaging algorithms
• Deep multi-redshift limits on Epoch of Reionisation 21cm Power Spectra from Four Seasons of Murchison Widefield Array Observations
• The impact of point source subtraction residuals on 21 cm Epoch of Reionization estimation
• First Results from HERA Phase I: Upper Limits on the Epoch of Reionization 21 cm Power Spectrum
• An Improved Model of Diffuse Galactic Radio Emission from 10 MHz to 5 THz
• Overcoming real-world obstacles in 21 cm power spectrum estimation: A method demonstration and results from early Murchison Widefield Array data
• All-Sky Interferometry with Spherical Harmonic Transit Telescopes
• Calibration Requirements for Detecting the 21 cm Epoch of Reionization Power Spectrum and Implications for the SKA
• First Season MWA EoR Power Spectrum Results at Redshift 7
• A study of fundamental limitations to statistical detection of redshifted HI from the epoch of reionization
• Foregrounds in Wide-Field Redshifted 21 cm Power Spectra
• Cosmic reionization after Planck
• A simplified, lossless re-analysis of PAPER-64
• Improving the Epoch of Reionization Power Spectrum Results from Murchison Widefield Array Season 1 Observations
• Precision Calibration of Radio Interferometers Using Redundant Baselines
• Revisiting the radio interferometer measurement equation. II. Calibration and direction-dependent effects
• The Evolution of 21-cm Structure (EOS): public, large-scale simulations of Cosmic Dawn and Reionization
• The Impact of Modeling Errors on Interferometer Calibration for 21 cm Power Spectra
• Light cone effect on the reionization 21-cm power spectrum
• The Global History of Reionisation
• The first power spectrum limit on the 21-cm signal of neutral hydrogen during the Cosmic Dawn at z=20-25 from LOFAR
• First Limits on the 21 cm Power Spectrum during the Epoch of X-ray heating
• Advances in Calibration and Imaging Techniques in Radio Interferometry
• A 189 MHz, 2400 square degree polarization survey with the Murchison Widefield Array 32-element prototype
• Fundamental Limitations on the Calibration of Redundant 21 cm Cosmology Instruments and Implications for HERA and the SKA
• Confirmation of Wide-Field Signatures in Redshifted 21 cm Power Spectra
• MITEoR: A Scalable Interferometer for Precision 21 cm Cosmology
• Mitigating Internal Instrument Coupling II: A Method Demonstration with the Hydrogen Epoch of Reionization Array
• Redundant Array Configurations for 21 cm Cosmology
• Characterizing Signal Loss in the 21 cm Reionization Power Spectrum: A Revised Study of PAPER-64
• Mitigating the Effects of Antenna-to-Antenna Variation on Redundant-Baseline Calibration for 21 cm Cosmology
• Understanding the Diversity of 21 cm Cosmology Analyses
• GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey II: Galactic Plane $345^{\circ }<l<67^{\circ }$, $180^{\circ }<l<240^{\circ }$
• Redundant-Baseline Calibration of the Hydrogen Epoch of Reionization Array
• Comparing Redundant and Sky Model Based Interferometric Calibration: A First Look with Phase II of the MWA
• Reionization inference from the CMB optical depth and E-mode polarization power spectra
• Cosmic Microwave Background Constraints in Light of Priors Over Reionization Histories
• Understanding the HERA Phase I receiver system with simulations and its impact on the detectability of the EoR delay power spectrum
• Absolute Calibration Strategies for the Hydrogen Epoch of Reionization Array and Their Impact on the 21 cm Power Spectrum
• Polarized Redundant-Baseline Calibration for 21 cm Cosmology Without Adding Spectral Structure
• Optimized Beam Sculpting with Generalized Fringe-Rate Filters
• Quantifying Suppression of the Cosmological 21-cm Signal due to Direction Dependent Gain Calibration in Radio Interferometers
• Patterns of primary beam non-redundancy in close-packed 21 cm array observations
• Array Element Coupling in Radio Interferometry I: A Semi-Analytic Approach
• A new parameterization of the reionisation history
• Lost Horizon: Quantifying the Effect of Local Topography on Global 21-cm Cosmology Data Analysis
• Design of the New Wideband Vivaldi Feed for the HERA Radio-Telescope Phase II
• The HERA-19 Commissioning Array: Direction Dependent Effects
• Quantifying EoR delay spectrum contamination from diffuse radio emission
• The Role of the Instrumental Response in 21 cm EoR Power Spectrum Gridding Analyses
• Effects of model incompleteness on the drift-scan calibration of radio telescopes

Cited by in corpus (6)

• Hydrogen Epoch of Reionization Array (HERA) Phase II Deployment and Commissioning
• Field-level Reconstruction from Foreground-Contaminated 21-cm Maps
• Exploring One-point Statistics in HERA Phase I Data: Effects of Foregrounds and Systematics on Measuring One-Point Statistics
• Primary Beam Chromaticity in HIRAX: I. Characterization from Simulations and Power Spectrum Implications
• The impact of lunar topography on the 21-cm power spectrum for grid-based arrays : Insights for the Dark-ages EXplorer (DEX)
• Mitigating gain calibration errors from EoR observations with SKA1-Low AA*