First upper limits on the 21 cm signal power spectrum from cosmic dawn from one night of observations with NenuFAR

Abstract

The redshifted 21 cm signal from neutral hydrogen is a direct probe of the physics of the early universe and has been an important science driver of many present and upcoming radio interferometers. In this study we use a single night of observations with the New Extension in Nançay Upgrading LOFAR (NenuFAR) to place upper limits on the 21 cm power spectrum from cosmic dawn at a redshift of $z$ = 20.3. NenuFAR is a new low-frequency radio interferometer, operating in the 10-85 MHz frequency range, currently under construction at the Nançay Radio Observatory in France. It is a phased array instrument with a very dense uv coverage at short baselines, making it one of the most sensitive instruments for 21 cm cosmology analyses at these frequencies. Our analysis adopts the foreground subtraction approach, in which sky sources are modeled and subtracted through calibration and residual foregrounds are subsequently removed using Gaussian process regression. The final power spectra are constructed from the gridded residual data cubes in the uv plane. Signal injection tests are performed at each step of the analysis pipeline, the relevant pipeline settings are optimized to ensure minimal signal loss, and any signal suppression is accounted for through a bias correction on our final upper limits. We obtain a best 2$\sigma$ upper limit of $2.4\times 10^7$ ${\text{mK}}^2$ at $z$ = 20.3 and $k$ = 0.041 $h{\text{cMpc}}^{-1}$. We see a strong excess power in the data, making our upper limits two orders of magnitude higher than the thermal noise limit. We investigate the origin and nature of this excess power and discuss further improvements to the analysis pipeline that can potentially mitigate it and consequently allow us to reach thermal noise sensitivity when multiple nights of observations are processed in the future.

arXiv comment27 pages, 21 figures, and 6 tables; accepted for publication in Astronomy and Astrophysics (A&A); language edits implemented; typos corrected

References in corpus (83)

• Planck 2015 results. XIII. Cosmological parameters
• LOFAR: The LOw-Frequency ARray
• Cosmology at Low Frequencies: The 21 cm Transition and the High-Redshift Universe
• An absorption profile centred at 78 megahertz in the sky-averaged spectrum
• 21-cm cosmology
• WSClean: an implementation of a fast, generic wide-field imager for radio astronomy
• The GMRT 150 MHz All-sky Radio Survey: First Alternative Data Release TGSS ADR1
• 21-cm Tomography of the Intergalactic Medium at High Redshift
• 21cmFAST: A Fast, Semi-Numerical Simulation of the High-Redshift 21-cm Signal
• Hydrogen Epoch of Reionization Array (HERA)
• Possible interaction between baryons and dark-matter particles revealed by the first stars
• Cosmological Parameter Estimation Using 21 cm Radiation from the Epoch of Reionization
• The VLA Low-frequency Sky Survey
• A morphological algorithm for improving radio-frequency interference detection
• A simulation calibrated limit on the HI power spectrum from the GMRT Epoch of Reionization experiment
• An optimized algorithm for multi-scale wideband deconvolution of radio astronomical images
• 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
• Insights on Dark Matter from Hydrogen during Cosmic Dawn
• 21 cm fluctuations from inhomogeneous X-ray heating before reionization
• Foreground simulations for the LOFAR - Epoch of Reionization Experiment
• Inferring the astrophysics of reionization and cosmic dawn from galaxy luminosity functions and the 21-cm signal
• The Spin-Kinetic Temperature Coupling and the Heating Rate due to Lyman Alpha Scattering before Reionization: Predictions for 21cm Emission and Absorption
• A Method for Separating the Physics from the Astrophysics of High-Redshift 21cm Fluctuations
• Enhanced global signal of neutral hydrogen due to excess radiation at cosmic dawn
• Toward Epoch of Reionization Measurements with Wide-Field Radio Observations
• Severely Constraining Dark Matter Interpretations of the 21-cm Anomaly
• Concerns about Modelling of the EDGES Data
• 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
• Modeling the Radio Background from the First Black Holes at Cosmic Dawn: Implications for the 21 cm Absorption Amplitude
• Radio interferometric gain calibration as a complex optimization problem
• First Results from HERA Phase I: Upper Limits on the Epoch of Reionization 21 cm Power Spectrum
• Signature of Excess Radio Background in the 21-cm Global Signal and Power Spectrum
• Calibration Requirements for Detecting the 21 cm Epoch of Reionization Power Spectrum and Implications for the SKA
• The GMRT-EoR Experiment: A new upper limit on the neutral hydrogen power spectrum at z~8.6
• Improved Constraints on the 21 cm EoR Power Spectrum and the X-Ray Heating of the IGM with HERA Phase I Observations
• Foreground Removal using FastICA: A Showcase of LOFAR-EoR
• Heating and Ionization of the Intergalactic Medium by an Early X-Ray Background
• Constraining Baryon--Dark Matter Scattering with the Cosmic Dawn 21-cm Signal
• 21cmFAST v3: A Python-integrated C code forgenerating 3D realizations of the cosmic 21cm signal
• Reviving Millicharged Dark Matter for 21-cm Cosmology
• A simplified, lossless re-analysis of PAPER-64
• Improving the Epoch of Reionization Power Spectrum Results from Murchison Widefield Array Season 1 Observations
• The Scale of the Problem : Recovering Images of Reionization with GMCA
• The Impact of the First Galaxies on Cosmic Dawn and Reionization
• The Radio Background Below 100 MHz
• First results on the Epoch of Reionization from First Light with SARAS 2
• The 21 cm Power Spectrum from the Cosmic Dawn: First Results from the OVRO-LWA
• Toward Empirical Constraints on the Global Redshifted 21 cm Brightness Temperature During the Epoch of Reionization
• Systematic biases in low frequency radio interferometric data due to calibration: the LOFAR EoR case
• 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
• First Season MWA Phase II EoR Power Spectrum Results at Redshift 7
• High-redshift radio galaxies: a potential new source of 21-cm fluctuations
• The rich complexity of 21-cm fluctuations produced by the first stars
• The Effects of Population III X-ray and Radio Backgrounds on the Cosmological 21-cm Signal
• A new MWA limit on the 21 cm Power Spectrum at Redshifts $\sim$ 13 $-$ 17
• A wide-band, active antenna system for long wavelength radio astronomy
• Results from EDGES High-Band: III. New Constraints on Parameters of the Early Universe
• Constraining the epoch of reionization with the variance statistic: simulations of the LOFAR case
• The impact of interference excision on 21-cm Epoch of Reionization power spectrum analyses
• Comparing Foreground Removal Techniques for Recovery of the LOFAR-EoR 21cm Power Spectrum
• SARAS 3 CD/EoR Radiometer: Design and Performance of the Receiver
• Gaussian Process Foreground Subtraction and Power Spectrum Estimation for 21 cm Cosmology
• Compression of interferometric radio-astronomical data
• A 21-cm power spectrum at 48 MHz, using the Owens Valley Long Wavelength Array
• Scintillation noise power spectrum and its impact on high redshift 21-cm observations
• Scintillation noise in widefield radio interferometry
• Impact of the Primordial Stellar Initial Mass Function on the 21-cm Signal
• Cobalt: A GPU-based correlator and beamformer for LOFAR
• The AARTFAAC Cosmic Explorer: observations of the 21-cm power spectrum in the EDGES absorption trough
• Quantifying Suppression of the Cosmological 21-cm Signal due to Direction Dependent Gain Calibration in Radio Interferometers
• Polarization leakage in epoch of reionization windows: II. Primary beam model and direction dependent calibration
• Polarization leakage in epoch of reionization windows: III. Wide-field effects of narrow-field arrays
• Wide-field LOFAR-LBA power-spectra analyses: Impact of calibration, polarization leakage and ionosphere
• Clustered Calibration: An Improvement to Radio Interferometric Direction Dependent Self-Calibration
• Precision requirements for interferometric gridding in 21-cm power spectrum analysis
• Constraining Warm Dark Matter and Pop III stars with the Global 21-cm Signal
• Assessing the impact of two independent direction-dependent calibration algorithms on the LOFAR 21-cm signal power spectrum
• Accurate modelling of the Lyman-$\alpha$ coupling for the 21-cm signal, observability with NenuFAR and SKA
• Degree-Scale Galactic Radio Emission at 122 MHz around the North Celestial Pole with LOFAR-AARTFAAC

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• Elevated UV luminosity density at Cosmic Dawn explained by non-evolving, weakly mass-dependent star formation efficiency
• Deeper multi-redshift upper limits on the Epoch of Reionization 21-cm signal power spectrum from LOFAR between z=8.3 and z=10.1
• How informative are summaries of the cosmic 21-cm signal?
• Beyond the horizon: Quantifying the full sky foreground wedge in the cylindrical power spectrum
• Forecasts and Statistical Insights for Line Intensity Mapping Cross-Correlations: A Case Study with 21cm x [CII]
• Wavelet Based Statistics for Enhanced 21cm EoR Parameter Constraints
• Constraints on the state of the IGM at $z\sim 8-10$ using redshifted 21-cm observations with LOFAR
• Simulation-Based Inference of the sky-averaged 21-cm signal from CD-EoR with REACH
• Improved upper limits on the 21-cm signal power spectrum at $z=17.0$ and $z=20.3$ from an optimal field observed with NenuFAR
• Cosmic mysteries and the hydrogen 21-cm line: bridging the gap with lunar observations
• Probing the intergalactic medium during the Epoch of Reionization using 21-cm signal power spectra
• Square Kilometre Array Science Data Challenge 3a: foreground removal for an EoR experiment
• Near-field imaging of local interference in radio interferometric data: Impact on the redshifted 21 cm power spectrum
• Ionospheric contributions to the excess power in high-redshift 21-cm power-spectrum observations with LOFAR
• Spectral modelling of Cygnus A between 110 and 250 MHz. Impact on the LOFAR 21-cm signal power spectrum
• Prospects for Observing High-redshift Radio-loud Quasars in the SKA Era: Paving the Way for 21-cm Forest Observations
• First upper limits on the 21-cm signal power spectrum of neutral hydrogen at $z=9.16$ from the LOFAR 3C196 field
• Broadband Polarized Radio Emission Detected from Starlink Satellites Below 100 MHz with NenuFAR
• Impact of the Epoch of Reionization sources on the 21-cm bispectrum
• A Differentiable, End-to-End Forward Model for 21 cm Cosmology: Estimating the Foreground, Instrument, and Signal Joint Posterior
• Robust direction-dependent gain-calibration of beam-modelling errors far from the target field
• Comparison of Bayesian inference methods using the Loreli II database of hydro-radiative simulations of the 21-cm signal
• The impact of lossy data compression on the power spectrum of the high redshift 21-cm signal with LOFAR
• Diffuse radio sky models using large scale shapelets
• A circularly polarized low-frequency radio burst from the exoplanetary system HD 189733
• Extracting the Epoch of Reionization Signal with 3D U-Net Neural Networks Using Data-driven Systematic Effect Model
• oLIMpus: An Effective Model for Line Intensity Mapping Auto- and Cross- Power Spectra in Cosmic Dawn and Reionization
• The Effect of Large Optical Depths on the Non-Gaussian 21-cm signal from Cosmic Dawn
• Analytical modeling of the one-dimensional power spectrum of 21-cm forest based on a halo model method
• The impact of lunar topography on the 21-cm power spectrum for grid-based arrays : Insights for the Dark-ages EXplorer (DEX)
• Sample Variance Denoising in Cylindrical 21-cm Power Spectra
• A New Boundary Condition on Reionization
• Beyond the Power Spectrum: A New Framework for Non-Stationary Fields with Applications to Light-Cone Effects in Line Intensity Mapping
• Mitigating incoherent excess variance in high-redshift 21 cm observations with multi-output cross-Gaussian process regression