Galaxy clusters enveloped by vast volumes of relativistic electrons

Abstract

The central regions of galaxy clusters are permeated by magnetic fields and filled with relativistic electrons. When clusters merge, the magnetic fields are amplified and relativistic electrons are re-accelerated by turbulence in the intra cluster medium. These electrons reach energies of 1 -- 10 GeV and, in the presence of magnetic fields, produce diffuse radio halos that typically cover an area of ~1 square Mpc. Here we report observations of four clusters whose radio halos are embedded in much more extended, diffuse radio emission, filling a volume 30 times larger than that of radio halos. The emissivity in these larger features is about 20 times lower than the emissivity in radio halos. We conclude that relativistic electrons and magnetic fields extend far beyond radio halos, and that the physical conditions in the outer regions of the clusters are quite different from those in the radio halos.

21 pages, 8 figures, Nature in press

References in corpus (52)

• LOFAR: The LOw-Frequency ARray
• 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
• The LOFAR Two-metre Sky Survey - II. First data release
• Cosmic rays in galaxy clusters and their non-thermal emission
• The LOFAR Two-metre Sky Survey -- V. Second data release
• Diffuse Radio Emission from Galaxy Clusters
• Turbulence and Magnetic Fields in the Large Scale Structure of the Universe
• Compressible Turbulence in Galaxy Clusters: Physics and Stochastic Particle Re-acceleration
• The Coma cluster magnetic field from Faraday rotation measures
• An optimized algorithm for multi-scale wideband deconvolution of radio astronomical images
• The Very Large Array Low-frequency Sky Survey Redux (VLSSr)
• 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
• Cluster mergers and non-thermal phenomena: expectations from a statistical magneto-turbulent model
• Halo and Relic Sources in Clusters of Galaxies
• Systematic effects in LOFAR data: A unified calibration strategy
• Universal thermodynamic properties of the intracluster medium over two decades in radius in the X-COP sample
• Radio interferometric gain calibration as a complex optimization problem
• GMRT Radio Halo Survey in galaxy clusters at z = 0.2 -- 0.4. II.The eBCS clusters and analysis of the complete sample
• LOFAR, VLA, and Chandra observations of the Toothbrush galaxy cluster
• Hydrodynamic Simulation of Non-thermal Pressure Profiles of Galaxy Clusters
• Acceleration of primary and secondary particles in galaxy clusters by compressible MHD turbulence: from radio halos to gamma rays
• Massive and Refined. II. The statistical properties of turbulent motions in massive galaxy clusters with high spatial resolution
• LOFAR observations of galaxy clusters in HETDEX
• Non-linear Kalman filters for calibration in radio interferometry
• Comparative analysis of the diffuse radio emission in the galaxy clusters A1835, A2029, and Ophiuchus
• Turbulence and Vorticity in Galaxy Clusters Generated by Structure Formation
• Turbulence and Particle Acceleration in Giant Radio Haloes: the Origin of Seed Electrons
• New scaling relations in cluster radio halos and the re-acceleration model
• Anticipated Performance of the Square Kilometre Array -- Phase 1 (SKA1)
• The Planck clusters in the LOFAR sky. I. LoTSS-DR2: new detections and sample overview
• The Matryoshka Run (II): Time Dependent Turbulence Statistics, Stochastic Particle Acceleration and Microphysics Impact in a Massive Galaxy Cluster
• The Non-Thermal Sunyaev-Zel'dovich Effect in Clusters of Galaxies
• Turbulence production and turbulent pressure support in the intergalactic medium
• Self-similar energetics in large clusters of galaxies
• LOFAR discovery of a double radio halo system in Abell 1758 and radio/X-ray study of the cluster pair
• Radio halos in a mass-selected sample of 75 galaxy clusters. II. Statistical analysis
• The two-component giant radio halo in the galaxy cluster Abell 2142
• A LOFAR study of non-merging massive galaxy clusters
• Dissecting nonthermal emission in the complex multiple-merger galaxy cluster Abell 2744: Radio and X-ray analysis
• A plethora of diffuse steep spectrum radio sources in Abell 2034 revealed by LOFAR
• The ultra-steep diffuse radio emission observed in the cool-core cluster RX J1720.1+2638 with LOFAR at 54 MHz
• New giant radio sources and underluminous radio halos in two galaxy clusters
• A Strong Merger Shock in Abell 665
• Further evidence for a merger in Abell 2218 from an XMM-Newton observation
• Investigating ionospheric calibration for LOFAR 2.0 with simulated observations
• Reaching thermal noise at ultra-low radio frequencies: the Toothbrush radio relic downstream of the shock front
• Radio halos in a mass-selected sample of 75 galaxy clusters. I. Sample selection and data analysis

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• LOFAR high-band antenna observations of the Perseus cluster
• A three-component giant radio halo: the puzzling case of the galaxy cluster Abell 2142
• Synchrotron Intensity Gradient Revealing Magnetic Fields in Galaxy Clusters
• Probing cluster magnetism with embedded and background radio sources in Planck clusters
• Investigating the turbulent hot gas in X-COP galaxy clusters
• Efficient micromirror confinement of sub-TeV cosmic rays in galaxy clusters
• A kiloparsec-scale ordered magnetic field in a galaxy at z=5.6
• The evolution of cosmic ray electrons in the cosmic web: seeding by AGN, star formation and shocks
• Radio halos and relics from extended cosmic-ray ion distributions with strong diffusion in galaxy clusters
• Simulating the LOcal Web (SLOW) -- III: Synchrotron emission from the local cosmic web
• Prospects for $\gamma$-ray observations of the Perseus galaxy cluster with the Cherenkov Telescope Array
• Probing particle acceleration in Abell 2256: from to 16 MHz to gamma rays
• Inflationary and phase-transitional primordial magnetic fields in galaxy clusters
• Magnetic dynamos in galaxy clusters: the crucial role of galaxy formation physics at high redshifts
• Thermal conductivity with bells and whistlers: suppression of the magnetothermal instability in galaxy clusters
• The MeerKAT Massive Distant Clusters Survey: A Radio Halo in a Massive Galaxy Cluster at z = 1.23
• Cosmological simulations of the generation of cluster-scale radio emission from turbulent re-acceleration
• Atacama Large Aperture Submillimeter Telescope (AtLAST) Science: Resolving the Hot and Ionized Universe through the Sunyaev-Zeldovich effect
• Constraints on the magnetic field in the inter-cluster bridge A399-A401
• Electron-Ion Equilibration in the Merging Galaxy Cluster A665
• Radio emission from a massive node of the cosmic web. A discovery powered by machine learning
• Mapping Diffuse Radio Sources Using TUNA: A Transformer-Based Deep Learning Approach
• MeerKAT discovery of GHz radio emission extending from Abell 3017 toward Abell 3016
• Revisiting Propagation Delays of Ultra-High-Energy Cosmic Rays from Long-lived Sources
• Discovery of large-scale radio emission enveloping the mini-halo in the most X-ray luminous galaxy cluster RX~J1347.5-1145
• uGMRT and MeerKAT observation of RXCJ0232-4420: a quiet cluster with a giant radio halo
• Cosmological simulation of a radio synchrotron bridge between pre-merging galaxy clusters
• Observations of the galaxy cluster CL 0217+70 and its surrounding region at 1.4 GHz with the Sardinia Radio Telescope