English
Related papers

Related papers: A study of halo and relic radio emission in mergin…

200 papers

Galaxy clusters have been found to host a range of diffuse, non-thermal emission components, generally with steep, power law spectra. In this work we report on the detection and follow-up of radio halos, relics, remnant radio galaxies, and…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-20 S. W. Duchesne , M. Johnston-Hollitt , I. Bartalucci

Pairs of radio relics are believed to form during cluster mergers, and are best observed when the merger occurs in the plane of the sky. Mergers can also produce radio halos, through complex processes likely linked to turbulent…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-26 A. Bonafede , R. Cassano , M. Brüggen , G. A. Ogrean , C. J. Riseley , V. Cuciti , F. de Gasperin , N. Golovich , R. Kale , T. Venturi , R. J van Weeren , D. R. Wik , D. Wittman

Radio observations over the last two decades have provided evidence that diffuse synchrotron emission in the form of megaparsec-scale radio halos in galaxy clusters is likely tracing regions of the intracluster medium where relativistic…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-25 G. Bernardi , T. Venturi , R. Cassano , D. Dallacasa , G. Brunetti , V. Cuciti , M. Johnston-Hollitt , N. Oozeer , O. M. Smirnov

Many galaxy clusters host Mpc scale diffuse radio sources called radio halos. Their origin is connected to the processes that lead to the formation of clusters themselves. In order to unveil this connection, statistical studies of radio…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-10 V. Cuciti , R. Cassano , G. Brunetti , D. Dallacasa , F. de Gasperin , S. Ettori , S. Giacintucci , R. Kale , G. W. Pratt , R. J. van Weeren , T. Venturi

A fraction of galaxy clusters host diffuse radio sources called radio halos, radio relics and mini-halos. We present the sample and first results from the Extended GMRT Radio Halo Survey (EGRHS)- an extension of the GMRT Radio Halo Survey…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 R. Kale , T. Venturi , S. Giacintucci , D. Dallacasa , R. Cassano , G. Brunetti , G. Macario , R. Athreya

We present new low-frequency ($\nu = 88$-216 MHz) observations of the complex merging galaxy cluster Abell 3266. These new observations are taken with the Murchison Widefield Array (MWA) in its Phase II 'extended', long-baseline…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-16 S. W. Duchesne , M. Johnston-Hollitt , C. J. Riseley , I. Bartalucci , S. R. Keel

We detect and characterise extended, diffuse radio emission from galaxy clusters at 168 MHz within the Epoch of Reionization 0-hour field: a $45^\circ \times 45^\circ$ region of the southern sky centred on R.~A.${}= 0^\circ$,…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-31 S. W. Duchesne , M. Johnston-Hollitt , A. R. Offringa , G. W. Pratt , Q. Zheng , S. Dehghan

Clusters of galaxies are the largest gravitationally bound objects in the Universe, containing about 10^15 solar masses of hot (10^8 K) gas, galaxies and dark matter in a typical volume of about 10 Mpc^3. Magnetic fields and relativistic…

The presence of megaparsec-scale radio halos in galaxy clusters has already been established by many observations over the last two decades. The emerging explanation for the formation of these giant sources of diffuse synchrotron radio…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-15 G. Bernardi , T. Venturi , R. Cassano , D. Dallacasa , G. Brunetti , V. Cuciti , M. Johnston-Hollitt , N. Oozeer , V. Parekh , O. M. Smirnov

In some clusters of galaxies, a diffuse non-thermal emission is present, not obviously associated with any individual galaxy. These sources have been identified as relics, mini-halos, and halos according to their properties and position…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 G. Giovannini , A. Bonafede , L. Feretti , F. Govoni , M. Murgia

Deep Very Large Array radio observations confirm the presence of halo and relic sources in six clusters of galaxies (A115, A520, A773, A1664, A2254, A2744) where a wide diffuse emission was previously found in the NRAO VLA Sky Survey. New…

Astrophysics · Physics 2009-11-06 F. Govoni , L. Feretti , G. Giovannini , H. Bohringer , T. H. Reiprich , M. Murgia

Upcoming radio telescopes will allow to study the radio sky at low frequencies with unprecedent sensitivity and resolution. New surveys are expected to discover a large number of new radio sources. Here we investigate the abundance of radio…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 S. E. Nuza , M. Hoeft , R. J. van Weeren , S. Gottloeber , G. Yepes

Context. It is well-established that shock waves in the intracluster medium launched by galaxy cluster mergers can produce synchrotron emission, which is visible to us at radio frequencies as radio relics. However, the particle acceleration…

We investigate the correlation between the integrated low-frequency and infrared (IR) emissions of star-forming galaxies extracted from the {\sl Herschel} Reference Survey. By taking advantage of the GaLactic Extragalactic All-sky MWA…

Astrophysics of Galaxies · Physics 2022-04-05 Tsutomu T. Takeuchi , Shuntaro A. Yoshida , Luca Cortese , O. Ivy Wong , Barbara Catinella , Suchetha Cooray

Hierarchical models of structure formation predict that galaxy clusters grow via mergers of smaller clusters and galaxy groups, as well as through continuous accretion of gas. MACS J0717.5+3745 is an X-ray luminous and complex merging…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 R. J. van Weeren , H. J. A. Rottgering , M. Bruggen , A. Cohen

Spectral index studies of halos, relics, and radio galaxies provide useful information on their origin and connection with merger processes. We present WSRT multi-wavelength observations of the galaxy cluster Abell 2255 at 25 cm, 85 cm, and…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 R. F. Pizzo , A. G. de Bruyn

We present a follow-up study focused on cluster-scale diffuse radio emissions in 115 galaxy clusters in the Southern sky, using full-resolution (7.8") and tapered low-resolution (15") images from the MeerKAT Galaxy Cluster Legacy Survey…

We present new, high frequency radio observations of the merging galaxy clusters PLCK G287.0+32.9, Abell 2744, and Bullet. These clusters are known to host $\sim$Mpc scale sources, known as radio halos, which are formed by the acceleration…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-20 K. Rajpurohit , A. Botteon , E. O'Sullivan , W. Forman , M. Balboni , L. Bruno , R. J. van Weeren , M. Hoeft , G. Brunetti , C. Jones , A. S. Rajpurohit , S. P. Sikhosana
‹ Prev 1 2 3 10 Next ›