The LWA1 Low Frequency Sky Survey

Abstract

We present a survey of the radio sky accessible from the first station of the Long Wavelength Array (LWA1). Images are presented at nine frequencies between 35 and 80 MHz with spatial resolutions ranging from $4.7^{\circ }$ to $2.0^{\circ }$, respectively. The maps cover the sky north of a declination of $-40^{\circ }$ and represent the most modern systematic survey of the diffuse Galactic emission within this frequency range. We also combine our survey with other low frequency sky maps to create an updated model of the low frequency sky. Due to the low frequencies probed by our survey, the updated model better accounts for the effects of free-free absorption from Galactic ionized Hydrogen. A longer term motivation behind this survey is to understand the foreground emission that obscures the redshifted 21 cm transition of neutral hydrogen from the cosmic dark ages ($z>10$) and, at higher frequencies, the epoch of reionization ($z>6$).

MNRAS accepted: 15 pages, 16 figures

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Cited by in corpus (50)

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• Design and characterization of the Large-Aperture Experiment to Detect the Dark Age (LEDA) radiometer systems
• The Radio Background Below 100 MHz
• The Radio Sky at Meter Wavelengths: m-Mode Analysis Imaging with the Owens Valley Long Wavelength Array
• Spectral Index of the Diffuse Radio Background Between 50 and 100 MHz
• Mapper of the IGM spin temperature: instrument overview
• A 21-cm power spectrum at 48 MHz, using the Owens Valley Long Wavelength Array
• The Radio Synchrotron Background: Conference Summary and Report
• The Second Radio Synchrotron Background Workshop: Conference Summary and Report
• Lunar Orbit Measurement of Cosmic Dawn 21 cm Global Spectrum
• An Ultra-long Wavelength Sky Model with Absorption Effect
• Spectral index of the Galactic foreground emission in the 50-87 MHz range
• Absolute Calibration of Diffuse Radio Surveys at 45 and 150 MHz
• Modelling the Galactic Foreground and Beam Chromaticity for Global 21-cm Cosmology
• Measuring the global 21-cm signal with the MWA-I: improved measurements of the Galactic synchrotron background using lunar occultation
• Exploiting synergies between JWST and cosmic 21-cm observations to uncover star formation in the early Universe
• Using the Long Wavelength Array to Search for Cosmic Dawn
• A General Bayesian Framework to Account for Foreground Map Errors in Global 21-cm Experiments
• Degree-Scale Galactic Radio Emission at 122 MHz around the North Celestial Pole with LOFAR-AARTFAAC
• Free-free absorption parameters of Cassiopeia A from low-frequency interferometric observations
• Effects of model incompleteness on the drift-scan calibration of radio telescopes
• A Simultaneous Dual-site Technosignature Search Using International LOFAR Stations
• A Differentiable, End-to-End Forward Model for 21 cm Cosmology: Estimating the Foreground, Instrument, and Signal Joint Posterior
• Pre-selection of the Candidate Fields for Deep Imaging of the Epoch of Reionization with SKA1-Low
• Bayesian evidence for flux scale errors in Galactic synchrotron maps
• Global Sky Models can Improve Flux Estimates in Pulsar and FRB Studies
• Scattering Parameter Measurements of the Long Wavelength Array Antenna and Front End Electronics
• The Orion-Taurus ridge: a synchrotron radio loop at the edge of the Orion-Eridanus superbubble
• Probing the global 21-cm background by velocity-induced dipole and quadrupole anisotropies
• Measuring the global 21-cm signal with the MWA-II: improved characterisation of lunar-reflected radio frequency interference
• Uncertainties of the 30-408 MHz Galactic emission as a calibration source for radio detectors in astroparticle physics
• Spectroscopy with the Engineering Development Array: cold H${}^{+}$ at 63 MHz towards the Galactic Centre
• Low-Frequency Radio Recombination Lines Away From the Inner Galactic Plane
• Narrowing the discovery space of the cosmological 21-cm signal using multi-wavelength constraints
• Synthetic Observations with the Square Kilometre Array (SKA) -- development towards an end-to-end pipeline
• A new analytical model of the cosmic-ray energy flux for Galactic diffuse radio emission
• The Optical Depth of Foregrounds for the Highest Redshift 21 cm Signals
• The Bayesian Global Sky Model (B-GSM): Validation of a Data Driven Bayesian Simultaneous Component Separation and Calibration Algorithm for EoR Foreground Modelling
• Pulsar Cyclic Spectroscopy in the Partial-Deconvolution Regime: Benefits & Limitations
• Design and Commissioning of an LWA Swarm Station: The Long Wavelength Array -- North Arm
• An Instrument Error Budget for Space-Based Absolute Flux Measurements of the Sky Synchrotron Spectrum Below 20 MHz
• Beamforming approaches toward detecting the 21-cm global signal from Cosmic Dawn with radio array telescopes
• The impact of lunar topography on the 21-cm power spectrum for grid-based arrays : Insights for the Dark-ages EXplorer (DEX)
• Bayesian recalibration of flux scale factors in diffuse radio maps using low-resolution absolute radiometers
• Spectral-line performance of low-frequency radio telescope arrays: SKA-Low stations
• RRAT-like behaviour of PSR B0656+14 observed with I-LOFAR
• Optimizing Foreground Modelling for Global 21cm Cosmology with GPU-Accelerated Nested Sampling
• Imaging the Southern Sky at 159MHz using Spherical Harmonics with the Engineering Development Array 2
• Measurements of the diffuse Galactic synchrotron spectral index and curvature from MeerKLASS pilot data