Understanding the HERA Phase I receiver system with simulations and its impact on the detectability of the EoR delay power spectrum

Abstract

The detection of the Epoch of Reionization (EoR) delay power spectrum using a "foreground avoidance method" highly depends on the instrument chromaticity. The systematic effects induced by the radio-telescope spread the foreground signal in the delay domain, which contaminates the EoR window theoretically observable. Applied to the Hydrogen Epoch of Reionization Array (HERA), this paper combines detailed electromagnetic and electrical simulations in order to model the chromatic effects of the instrument, and quantify its frequency and time responses. In particular, the effects of the analogue receiver, transmission cables, and mutual coupling are included. These simulations are able to accurately predict the intensity of the reflections occurring in the 150-m cable which links the antenna to the back-end. They also show that electromagnetic waves can propagate from one dish to another one through large sections of the array due to mutual coupling. The simulated system time response is attenuated by a factor $10^4$ after a characteristic delay which depends on the size of the array and on the antenna position. Ultimately, the system response is attenuated by a factor $10^5$ after 1400 ns because of the reflections in the cable, which corresponds to characterizable $k_{\parallel }$-modes above 0.7 $h{\mathrm{Mpc}}^{-1}$ at 150 MHz. Thus, this new study shows that the detection of the EoR signal with HERA Phase I will be more challenging than expected. On the other hand, it improves our understanding of the telescope, which is essential to mitigate the instrument chromaticity.

arXiv comment13 pages, 17 figures - Submitted to MNRAS - 2nd revision

References in corpus (36)

• LOFAR: The LOw-Frequency ARray
• The Murchison Widefield Array: the Square Kilometre Array Precursor at low radio frequencies
• 21-cm cosmology
• Hydrogen Epoch of Reionization Array (HERA)
• Reionization and Cosmology with 21 cm Fluctuations
• The Precision Array for Probing the Epoch of Reionization: 8 Station Results
• The morphology of HII regions during reionization
• What Next-Generation 21 cm Power Spectrum Measurements Can Teach Us About the Epoch of Reionization
• A Per-Baseline, Delay-Spectrum Technique for Accessing the 21cm Cosmic Reionization Signature
• The Epoch of Reionization Window: I. Mathematical Formalism
• PAPER-64 Constraints on Reionization: The 21cm Power Spectrum at z=8.4
• A Sensitivity and Array-Configuration Study for Measuring the Power Spectrum of 21cm Emission from Reionization
• Overcoming real-world obstacles in 21 cm power spectrum estimation: A method demonstration and results from early Murchison Widefield Array data
• Foreground Contamination in Interferometric Measurements of the Redshifted 21 cm Power Spectrum
• Foreground Removal using FastICA: A Showcase of LOFAR-EoR
• 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
• Precision Calibration of Radio Interferometers Using Redundant Baselines
• The Impact of Modeling Errors on Interferometer Calibration for 21 cm Power Spectra
• Power spectrum extraction for redshifted 21-cm epoch of reionization experiments: the LOFAR case
• Confirmation of Wide-Field Signatures in Redshifted 21 cm Power Spectra
• Reionization and Beyond: detecting the peaks of the cosmological 21cm signal
• PAPER-64 Constraints On Reionization II: The Temperature Of The z=8.4 Intergalactic Medium
• A Scalable Correlator Architecture Based on Modular FPGA Hardware, Reuseable Gateware, and Data Packetization
• Effects of Antenna Beam Chromaticity on Redshifted 21~cm Power Spectrum and Implications for Hydrogen Epoch of Reionization Array
• Mitigating Internal Instrument Coupling II: A Method Demonstration with the Hydrogen Epoch of Reionization Array
• Redundant Array Configurations for 21 cm Cosmology
• The Murchison Widefield Array 21 cm Power Spectrum Analysis Methodology
• Mitigating the Effects of Antenna-to-Antenna Variation on Redundant-Baseline Calibration for 21 cm Cosmology
• 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
• The Hydrogen Epoch of Reionization Array Dish II: Characterization of Spectral Structure with Electromagnetic Simulations and its science Implications
• The 21-cm Line as a Probe of Reionization
• Design of the New Wideband Vivaldi Feed for the HERA Radio-Telescope Phase II
• Measuring HERA's primary beam in-situ: methodology and first results
• The Hydrogen Epoch of Reionization Array Dish III: Measuring Chromaticity of Prototype Element with Reflectometry

Cited by in corpus (31)

• First Results from HERA Phase I: Upper Limits on the Epoch of Reionization 21 cm Power Spectrum
• Improved Constraints on the 21 cm EoR Power Spectrum and the X-Ray Heating of the IGM with HERA Phase I Observations
• Redundant-Baseline Calibration of the Hydrogen Epoch of Reionization Array
• DAYENU: A Simple Filter of Smooth Foregrounds for Intensity Mapping Power Spectra
• 21cmEMU: an emulator of 21cmFAST summary observables
• Patterns of primary beam non-redundancy in close-packed 21 cm array observations
• Hydrogen Epoch of Reionization Array (HERA) Phase II Deployment and Commissioning
• Array Element Coupling in Radio Interferometry I: A Semi-Analytic Approach
• Validation of the HERA Phase I Epoch of Reionization 21 cm Power Spectrum Software Pipeline
• Design of the New Wideband Vivaldi Feed for the HERA Radio-Telescope Phase II
• Statistical recovery of 21cm visibilities and their power spectra with Gaussian constrained realisations and Gibbs sampling
• The Impact of Beam Variations on Power Spectrum Estimation for 21-cm Cosmology I: Simulations of Foreground Contamination for HERA
• Evidence of Ultra-faint Radio Frequency Interference in Deep 21~cm Epoch of Reionization Power Spectra with the Murchison Widefield Array
• Exploring the cosmic dawn and epoch of reionization with 21cm line
• A Bayesian approach to high fidelity interferometric calibration II: demonstration with simulated data
• On the use of temporal filtering for mitigating galactic synchrotron calibration bias in 21 cm reionization observations
• Impact of instrument and data characteristics in the interferometric reconstruction of the 21 cm power spectrum
• SKA-Low Intensity Mapping Pathfinder Updates: Deeper 21 cm Power Spectrum Limits from Improved Analysis Frameworks
• All Sky Modelling Requirements for Bayesian 21 cm Power Spectrum Estimation with BayesEoR
• Direct Optimal Mapping for 21cm Cosmology: A Demonstration with the Hydrogen Epoch of Reionization Array
• Effects of model incompleteness on the drift-scan calibration of radio telescopes
• Search for the Epoch of Reionisation with HERA: Upper Limits on the Closure Phase Delay Power Spectrum
• Sensitivity of Bayesian 21 cm power spectrum estimation to foreground model errors
• Characterizing Beam Errors for Radio Interferometric Observations of Reionization
• The Statistics of Negative Power Spectrum Systematics in some 21 cm Analyses
• Simulations of primary beam effects on the cosmic bispectrum phase observed with the Hydrogen Epoch of Reionization Array
• Synthetic Observations with the Square Kilometre Array (SKA) -- development towards an end-to-end pipeline
• Exploring One-point Statistics in HERA Phase I Data: Effects of Foregrounds and Systematics on Measuring One-Point Statistics
• Establishing a relationship between the cosmological 21 cm power spectrum and interferometric closure phases
• The Effects of the Local Environment on a Compact Radio Interferometer I: Cross-coupling in the Tianlai Dish Pathfinder Array
• A Bayesian approach to high fidelity interferometric calibration I: mathematical formalism