The LOFAR and JVLA view of the distant steep spectrum radio halo in MACS J1149.5+2223

Abstract

Radio halos and relics are Mpc-scale diffuse radio sources in galaxy clusters, with a steep spectral index $\alpha >1$ ($S\propto {\nu }^{-\alpha }$). It has been proposed that they arise from particle acceleration induced by turbulence and weak shocks, injected in the intracluster medium (ICM) during mergers. MACS J1149.5+2223 (MACS J1149) is a high redshift ($z=0.544$) galaxy cluster possibly hosting a radio halo and a relic. We analysed LOFAR, GMRT, and JVLA radio data at 144, 323, 1500 MHz, and Chandra X-ray data to characterise the thermal and non-thermal properties of the cluster. We obtained radio images at different frequencies to investigate the spectral properties of the radio halo. We used Chandra X-ray images to constrain the thermal properties of the cluster. We measured a steep spectrum of the halo, with $\alpha =1.49\pm 0.12$ between 144 and 1500 MHz. The radio surface brightness distribution across the halo is found to correlate with the X-ray brightness of the ICM, with a sub-linear slope in the range 0.4 to 0.6. We also report two possible cold fronts in north-east and north-west, but deeper X-ray observations are required to firmly constrain the properties of the upstream emission. We show that the combination of high redshift, steep radio spectrum, and sub-linear radio-X scaling of the halo rules out hadronic models. An old ($\sim 1$ Gyr ago) major merger likely induced the formation of the halo through stochastic re-acceleration of relativistic electrons. We suggest that the two possible X-ray discontinuities may actually be part of the same cold front. In this case, the coolest gas pushed towards the north-west might be associated with the cool core of a sub-cluster involved in the major merger. The peculiar orientation of the south-east relic might indicate a different nature of this source and requires further investigation.

arXiv comment15 pages, accepted for publication in A&A

References in corpus (97)

• LOFAR: The LOw-Frequency ARray
• Some Aspects of Measurement Error in Linear Regression of Astronomical Data
• 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
• Calibration of X-ray absorption in our Galaxy
• Linear Regression for Astronomical Data with Measurement Errors and Intrinsic Scatter
• Subaru Prime Focus Camera -- Suprime-Cam --
• The LOFAR Two-metre Sky Survey - I. Survey Description and Preliminary Data Release
• 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
• MACS: A quest for the most massive galaxy clusters in the universe
• Planck 2015 results. XXIV. Cosmology from Sunyaev-Zeldovich cluster counts
• Diffuse Radio Emission from Galaxy Clusters
• On The Non Thermal Emission and Acceleration of Electrons in Coma and Other Clusters of Galaxies
• An Accurate Flux Density Scale from 1 to 50 GHz
• Compressible Turbulence in Galaxy Clusters: Physics and Stochastic Particle Re-acceleration
• The Coma cluster magnetic field from Faraday rotation measures
• A morphological algorithm for improving radio-frequency interference detection
• Ionospheric Calibration of Low Frequency Radio Interferometric Observations using the Peeling Scheme: I. Method Description and First Results
• On the connection between giant radio halos and cluster mergers
• Bow shock and radio halo in the merging cluster A520
• An optimized algorithm for multi-scale wideband deconvolution of radio astronomical images
• Cosmic Rays, Radio Halos and Non-Thermal X-ray Emission in Clusters of Galaxies
• 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
• The LOFAR Two Meter Sky Survey: Deep Fields, I -- Direction-dependent calibration and imaging
• Faceting for direction-dependent spectral deconvolution
• The Cool-Core Bias in X-ray Galaxy Cluster Samples I: Method And Application To HIFLUGCS
• A Comparison of Radio and X-Ray Morphologies of Four Clusters of Galaxies Containing Radio Halos
• Contour binning: a new technique for spatially-resolved X-ray spectroscopy applied to Cassiopeia A
• A Cluster Merger and the Origin of the Extended Radio Emission in Abell 3667
• Revisiting scaling relations for giant radio halos in galaxy clusters
• Systematic effects in LOFAR data: A unified calibration strategy
• Radio interferometric gain calibration as a complex optimization problem
• The Case for Electron Re-Acceleration at Galaxy Cluster Shocks
• Diffusive Shock Acceleration Simulations of Radio Relics
• Statistics of Giant Radio Halos from Electron Reacceleration Models
• Acceleration of primary and secondary particles in galaxy clusters by compressible MHD turbulence: from radio halos to gamma rays
• Giant radio relics in galaxy clusters: reacceleration of fossil relativistic electrons?
• Simulating cosmic rays in clusters of galaxies - II. A unified scheme for radio halos and relics with predictions of the gamma-ray emission
• Search for cosmic-ray induced gamma-ray emission in Galaxy Clusters
• Discovery of radio halos and double-relics in distant MACS galaxy clusters: clues to the efficiency of particle acceleration
• Evidence for AGN Feedback in Galaxy Clusters and Groups
• Evidence for particle re-acceleration in the radio relic in the galaxy cluster PLCKG287.0 +32.9
• LOFAR observations of galaxy clusters in HETDEX
• Rise and Fall of Radio Halos in Simulated Merging Galaxy Clusters
• The giant radio halo in Abell 2163
• Non-linear Kalman filters for calibration in radio interferometry
• The late time radio emission from SN 1993J at meter wavelengths
• Stochastic reacceleration of relativistic electrons by turbulent reconnection: a mechanism for cluster-scale radio emission ?
• Shock acceleration efficiency in radio relics
• Search for gamma-ray emission from the Coma Cluster with six years of Fermi-LAT data
• A High Fidelity Sample of Cold Front Clusters from the Chandra Archive
• Turbulence and Particle Acceleration in Giant Radio Haloes: the Origin of Seed Electrons
• A very deep Chandra view of metals, sloshing and feedback in the Centaurus cluster of galaxies
• On the occurrence of Radio Halos in galaxy clusters - Insight from a mass-selected sample
• Alfvenic reacceleration of relativistic particles in galaxy clusters in the presence of secondary electrons and positrons
• Shock heating of the merging galaxy cluster A521
• Relativistic protons in the Coma galaxy cluster: first gamma-ray constraints ever on turbulent reacceleration
• Probing the origin of giant radio halos through radio and gamma-ray data : the case of the Coma cluster
• Unveiling radio halos in galaxy clusters in the LOFAR era
• The Matryoshka Run (II): Time Dependent Turbulence Statistics, Stochastic Particle Acceleration and Microphysics Impact in a Massive Galaxy Cluster
• The LOFAR radio environment
• Detecting edges in the X-ray surface brightness of galaxy clusters
• The beautiful mess in Abell 2255
• A shock at the radio relic position in Abell 115
• Spectral properties and origin of the radio halo in A3562
• A $\mathcal{M}\gtrsim 3$ shock in `El Gordo' cluster and the origin of the radio relic
• Deep LOFAR observations of the merging galaxy cluster CIZA J2242.8+5301
• LOFAR discovery of an ultra-steep radio halo and giant head-tail radio galaxy in Abell 1132
• The Extended GMRT Radio Halo Survey I: New upper limits on radio halos and mini-halos
• Shocks and cold fronts in merging and massive galaxy clusters: new detections with Chandra
• Constraints on diffuse gamma-ray emission from structure formation processes in the Coma cluster
• A shock front at the radio relic of Abell 2744
• Low frequency follow up of radio halos and relics in the GMRT Radio Halo Cluster Survey
• On the connection between turbulent motions and particle acceleration in galaxy clusters
• Chandra ACIS-I particle background: an analytical model
• Deep Westerbork observations of Abell 2256 at 350 MHz
• The very steep spectrum radio halo in Abell 697
• Merging Cluster Collaboration: A Panchromatic Atlas of Radio Relic Mergers
• Radio observations of the merging galaxy cluster Abell 520
• Deep 1.4 GHZ Follow Up of the Steep Spectrum Radio Halo in Abell 521
• Suzaku observations of the merging galaxy cluster Abell2255: The northeast radio relic
• Dynamical state for 964 galaxy clusters from Chandra X-ray images
• Radio and X-ray connection in radio mini-halos: implications for hadronic models
• An azimuthally resolved study of the cold front in Abell 3667
• X-ray study of the double radio relic Abell 3376 with Suzaku
• The discovery of radio halos in the Frontier Fields clusters Abell S1063 and Abell 370
• Applying Wirtinger derivatives to the radio interferometry calibration problem
• MC${}^2$: Dynamical Analysis of the Merging Galaxy Cluster MACS J1149.5+2223
• MHD Turbulence and Cosmic Ray Reacceleration in Galaxy Clusters
• A Massive Cluster at z = 0.288 Caught in the Process of Formation: The Case of Abell 959
• Frontier Fields Clusters: Deep Chandra Observations of the Complex Merger MACS J1149.6+2223
• Diffuse Radio Sources in a Statistically Complete Sample of High Redshift Galaxy Clusters
• Constraining relativistic protons and magnetic fields in galaxy clusters through radio and gamma-ray observations : the case of A2256

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• Dissecting nonthermal emission in the complex multiple-merger galaxy cluster Abell 2744: Radio and X-ray analysis
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• A MeerKAT-meets-LOFAR Study of MS 1455.0+2232: A 590 kiloparsec 'Mini'-Halo in a Sloshing Cool-Core Cluster
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• Combined LOFAR-uGMRT analysis of the diffuse radio emission in the massive clusters Abell 773 and Abell 1351
• uGMRT and MeerKAT observation of RXCJ0232-4420: a quiet cluster with a giant radio halo
• A LOFAR-uGMRT spectral index study of distant radio halos
• Low-frequency integrated radio spectra of diffuse, steep-spectrum sources in galaxy clusters: palaeontology with the MWA and ASKAP