English
Related papers

Related papers: Discovering the most elusive radio relic in the sk…

200 papers

Double radio relics in galaxy clusters are rare phenomena that trace shocks in the outskirts of merging galaxy clusters. We have carried out a spectral and polarization study of the spectacular double relics in the galaxy cluster A3376…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Ruta Kale , K. S. Dwarakanath , Joydeep Bagchi , Surajit Paul

We perform a systematic X-ray analysis of six giant radio relics in four clusters of galaxies using the Suzaku satellite. The sample includes CIZA 2242.8-5301, Zwcl 2341.1-0000, the South-East part of Abell 3667 and previously published…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-02 Hiroki Akamatsu , Hajime Kawahara

In this Letter, we report the discovery of a radio halo in the high-redshift galaxy cluster PSZ2 G099.86+58.45 ($z=0.616$) with the LOw Frequency ARray (LOFAR) at 120-168 MHz. This is one of the most distant radio halos discovered so far.…

Diffuse radio emission in the form of radio halos and relics has been found in a number of merging galaxy clusters. These structures indicate that shock and turbulence associated with the merger accelerate electrons to relativistic…

High Energy Astrophysical Phenomena · Physics 2015-09-23 F. de Gasperin , H. T. Intema , R. J. van Weeren , W. A. Dawson , N. Golovich , D. Wittman , A. Bonafede , M. Bruggen

We discuss a new technique to constrain models for the origin of radio relics in galaxy clusters using the correlation between the shock Mach number and the radio power of relics. This analysis is carried out using a sample of relics with…

High Energy Astrophysical Phenomena · Physics 2017-07-26 S. Colafrancesco , P. Marchegiani , C. M. Paulo

Radio relics are diffuse synchrotron sources in galaxy clusters that are believed to trace large-scale shock waves. We have discovered a new double radio relic system in PSZ1 G096.89+24.17 (z=0.3) and have carried out a full-polarization…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 F. de Gasperin , R. J. van Weeren , M. Bruggen , F. Vazza , A. Bonafede , H. T. Intema

We report upgraded Giant Metrewave Radio Telescope and Karl J. Jansky Very Large Array radio observations of a low-mass merging galaxy cluster PSZ2 G181.06+48.47. This exceptional galaxy cluster hosts two megaparsec-scale diffuse sources,…

According to structure formation simulations, weak shocks with typical Mach number, $M_{\rm s}\lesssim 3$, are expected to form in merging galaxy clusters. The presence of such shocks has been indicated by X-ray and radio observations of…

High Energy Astrophysical Phenomena · Physics 2017-07-26 Hyesung Kang , Dongsu Ryu , T. W. Jones

The relation between giant radio halos and mini-halos in galaxy clusters is not understood. The former are usually associated with merging clusters, the latter are found in relaxed systems. In the last years, the advent of low-frequency…

High sensitivity of modern interferometers is revealing a plethora of filaments surrounding radio galaxies, especially in galaxy cluster environments. The morphology and spectral characteristics of these thin structures require the…

We analyzed a deep Chandra observation (334 ks) of the galaxy cluster Abell 115 and detected a shock co-spatial with the radio relic. The X-ray surface brightness profile across the shock region presents a discontinuity, corresponding to a…

High Energy Astrophysical Phenomena · Physics 2016-05-02 A. Botteon , F. Gastaldello , G. Brunetti , D. Dallacasa

With Australia Telescope Compact Array observations, we detect a highly elongated Mpc-scale diffuse radio source on the eastern periphery of the Bullet cluster 1E0657-55.8, which we argue has the positional, spectral and polarimetric…

High Energy Astrophysical Phenomena · Physics 2016-03-23 Timothy W. Shimwell , Maxim Markevitch , Shea Brown , Luigina Feretti , B. M. Gaensler , M. Johnston-Hollitt , Craig Lage , Raghav Srinivasan

Massive, merging galaxy clusters often host giant, diffuse radio sources that arise from shocks and turbulence; hence, radio observations can be useful for determining the merger state of a cluster. In preparation for a larger study, we…

We report the discovery of large-scale diffuse radio emission in the galaxy cluster MACS J1752.0+4440 (z=0.366). Using Westerbork Synthesis Radio Telescope (WSRT) observations we find that the cluster hosts a double radio relic system as…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 R. J. van Weeren , A. Bonafede , H. Ebeling , A. C. Edge , M. Bruggen , G. Giovannini , M. Hoeft , H. J. A. Rottgering

Recent radio observations with Low-Frequency Array (LOFAR) discovered diffuse emission extending beyond the scale of classical radio halos. The presence of such mega halos indicates that the amplification of the magnetic field and…

High Energy Astrophysical Phenomena · Physics 2023-12-05 Kosuke Nishiwaki , Gianfranco Brunetti , Franco Vazza , Claudio Gheller

We present a 6GHz radio continuum image of the galaxy cluster Abell 2744 ($z = 0.307$) obtained with the Karl G. Jansky Very Large Array (VLA) as part of the VLA Frontier Fields program, whose goal is to explore the radio continuum emission…

We report a discovery of a double radio relic in the cluster merger ZwCl1447.2+2619 ($z=0.376$) with uGMRT observations at $420\rm~MHz$ and $700\rm~MHz$. The linear sizes of the northern and southern relics are $\sim0.3~$Mpc and…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-12 Wonki Lee , M. James Jee , Kyle Finner , Kim HyeongHan , Ruta Kale , Hyein Yoon , William Forman , Ralph Kraft , Christine Jones , Aeree Chung

We present 74 MHz and 330 MHz VLA observations of Abell 754. Diffuse, halo-like emission is detected from the center of the cluster at both frequencies. At 330 MHz the resolution of 90'' distinguishes this extended emission from previously…

Astrophysics · Physics 2009-11-06 N. E. Kassim , T. E. Clarke , T. A. Enßlin , A. S. Cohen , D. M. Neumann

A number of radio observations have revealed the presence of large synchrotron-emitting sources associated with the intra-cluster medium. There is strong observational evidence that the emitting particles have been (re-)accelerated by…

Context: Hierarchical galaxy formation models indicate that during their lifetime galaxy clusters undergo several mergers. Here we report on the discovery of three diffuse radio sources in the periphery of Abell 2256, using the GMRT. Aims:…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 R. J. van Weeren , H. T. Intema , J. B. R. Oonk , H. J. A. Rottgering , T. E. Clarke
‹ Prev 1 4 5 6 7 8 10 Next ›