LOFAR Detection of a Low-Power Radio Halo in the Galaxy Cluster Abell 990

Abstract

Radio halos are extended ($\sim \mathrm{Mpc}$), steep-spectrum sources found in the central region of dynamically disturbed clusters of galaxies. Only a handful of radio halos have been reported to reside in galaxy clusters with a mass $M_{500}\lesssim 5\times 10^{14}{M}_{\odot }$. In this paper we present a LOFAR 144 MHz detection of a radio halo in the galaxy cluster Abell 990 with a mass of $M_{500}=(4.9\pm 0.3)\times 10^{14}{M}_{\odot }$. The halo has a projected size of $\sim$700$\mathrm{kpc}$ and a flux density of $20.2\pm 2.2\mathrm{mJy}$ or a radio power of $1.2\pm 0.1\times 10^{24}{\mathrm{W}\mathrm{Hz}}^{-1}$ at the cluster redshift ($z=0.144$) which makes it one of the two halos with the lowest radio power detected to date. Our analysis of the emission from the cluster with Chandra archival data using dynamical indicators shows that the cluster is not undergoing a major merger but is a slightly disturbed system with a mean temperature of $5\mathrm{keV}$. The low X-ray luminosity of $L_X=(3.66\pm 0.08)\times 10^{44}{\mathrm{ergs}\mathrm{s}}^{-1}$ in the 0.1--2.4 keV band implies that the cluster is one of the least luminous systems known to host a radio halo. Our detection of the radio halo in Abell 990 opens the possibility of detecting many more halos in poorly-explored less-massive clusters with low-frequency telescopes such as LOFAR, MWA (Phase II) and uGMRT.

References in corpus (69)

• LOFAR: The LOw-Frequency ARray
• The Eleventh and Twelfth Data Releases of the Sloan Digital Sky Survey: Final Data from SDSS-III
• Collisional Plasma Models with APEC/APED: Emission Line Diagnostics of Hydrogen-like and Helium-like Ions
• HI4PI: A full-sky HI survey based on EBHIS and GASS
• 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
• The LOFAR Two-metre Sky Survey - I. Survey Description and Preliminary Data Release
• Clusters of galaxies : observational properties of the diffuse radio emission
• The LOFAR Two-metre Sky Survey - II. First data release
• Cosmic rays in galaxy clusters and their non-thermal emission
• Particle reacceleration in Coma cluster: radio properties and hard X-ray emission
• Diffuse Radio Emission from Galaxy Clusters
• On The Non Thermal Emission and Acceleration of Electrons in Coma and Other Clusters of Galaxies
• Compressible Turbulence in Galaxy Clusters: Physics and Stochastic Particle Re-acceleration
• A morphological algorithm for improving radio-frequency interference detection
• An Accurate Flux Density Scale from 50 MHz to 50 GHz
• On the connection between giant radio halos and cluster mergers
• Planck 2015 results. XXVII. The Second Planck Catalogue of Sunyaev-Zeldovich Sources
• Radio Halo and Relic Candidates from the NRAO VLA Sky Survey
• The impact of mergers on relaxed X-ray clusters - I. Dynamical evolution and emergent transient structures
• A broadband flux scale for low frequency radio telescopes
• LOFAR facet calibration
• A low-frequency radio halo associated with a cluster of galaxies
• LOFAR 150-MHz observations of the Boötes field: Catalogue and Source Counts
• Faceting for direction-dependent spectral deconvolution
• The Phase II Murchison Widefield Array: Design Overview
• Searching for Cool Core Clusters at High redshift
• Revisiting scaling relations for giant radio halos in galaxy clusters
• Measuring the Ultimate Mass of Galaxy Clusters: Redshifts and Mass Profiles from the Hectospec Cluster Survey (HeCS)
• Systematic effects in LOFAR data: A unified calibration strategy
• Radio interferometric gain calibration as a complex optimization problem
• Statistics of Giant Radio Halos from Electron Reacceleration Models
• Quantifying the Morphologies and Dynamical Evolution of Galaxy Clusters. I. The Method
• GeV Gamma-ray Flux Upper Limits from Clusters of Galaxies
• Deep images of cluster radio halos
• LOFAR/H-ATLAS: A deep low-frequency survey of the Herschel-ATLAS North Galactic Pole field
• A uniform metal distribution in the intergalactic medium of the Perseus cluster of galaxies
• Rise and Fall of Radio Halos in Simulated Merging Galaxy Clusters
• Substructure of the galaxy clusters in the REXCESS sample: observed statistics and comparison to numerical simulations
• Non-linear Kalman filters for calibration in radio interferometry
• Substructure and dynamical state of 2092 rich clusters of galaxies derived from photometric data
• Search for gamma-ray emission from the Coma Cluster with six years of Fermi-LAT data
• On the occurrence of Radio Halos in galaxy clusters - Insight from a mass-selected sample
• Relativistic protons in the Coma galaxy cluster: first gamma-ray constraints ever on turbulent reacceleration
• Unveiling radio halos in galaxy clusters in the LOFAR era
• A giant radio halo in the cool core cluster CL1821+643
• Spectral properties and origin of the radio halo in A3562
• Radio Halos in future surveys in the radio continuum
• On the Physics of Radio Halos in Galaxy Clusters: Scaling Relations and Luminosity Functions
• Radio Properties of the Shapley Concentration. III. Merging Clusters in the A3558 Complex
• Estimating galaxy cluster magnetic fields by the classical and hadronic minimum energy criterion
• A LOFAR study of non-merging massive galaxy clusters
• On the absence of radio halos in clusters with double relics
• The radio halo in the merging cluster A3562
• Characterization of ICM Temperature Distributions of 62 Galaxy Clusters with XMM-Newton
• Compression of interferometric radio-astronomical data
• An Objective Survey of Mpc-Scale Radio Emission in 0.03<z<0.3 Bright X-ray Clusters
• Particle acceleration in a nearby galaxy cluster pair: the role of cluster dynamics
• Brightest Cluster Galaxies in the Extended GMRT radio halo cluster sample. Radio properties and cluster dynamics
• KAT-7 observations of a mass-selected sample of galaxy clusters
• Radio halos in SZ-selected clusters of galaxies: the making of a halo?
• ATCA observations of the MACS-Planck Radio Halo Cluster Project - I. New detection of a radio halo in PLCK G285.0-23.7
• Mystery solved: discovery of extended radio emission in the merging galaxy cluster Abell 2146
• Characterizing the radio emission from the binary galaxy cluster merger Abell 2146
• A Massive Cluster at z = 0.288 Caught in the Process of Formation: The Case of Abell 959
• LOFAR discovery of a radio halo in the high-redshift galaxy cluster PSZ2 G099.86+58.45
• On the variance of radio interferometric calibration solutions: Quality-based Weighting Schemes
• A Chandra Study of Radial Temperature Profiles of the Intra-Cluster Medium in 50 Galaxy Clusters
• The Galaxy Cluster 'Pypeline' for X-ray Temperature Maps: ClusterPyXT

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• The Planck clusters in the LOFAR sky. I. LoTSS-DR2: new detections and sample overview
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