576 citations · 12k across the 198 of their papers we have counts for
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Gamma ray emission and stochastic particle acceleration in galaxy clusters
G. Brunetti, P. Blasi, R. Cassano +1
FERMI (formely GLAST) will shortly provide crucial information on relativistic particles in galaxy clusters. We discuss non-thermal emission in the context of general calculations…
A low-frequency radio halo associated with a cluster of galaxies
G. Brunetti, S. Giacintucci, R. Cassano +7
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 v…
NIR/Optical Counterparts of Hotspots in Radio Galaxies
K. -H. Mack, M. A. Prieto, G. Brunetti +1
We present new high spatial resolution VLT and VLA observations of a sample of nine low-power (P_{1.4 GHz} < 10^{25} W/Hz) radio hotspots. Infrared/optical emission is definitely d…
A high resolution view of the jet termination shock in a hot spot of the nearby radio galaxy Pictor A: implications for X-ray models of radio galaxy hot spots
S. J. Tingay, E. Lenc, G. Brunetti +1
Images made with the VLBA have resolved the region in a nearby radio galaxy, Pictor A, where the relativistic jet that originates at the nucleus terminates in an interaction with t…
Shock Waves in Eulerian Cosmological Simulations: Main Properties and Acceleration of Cosmic Rays
F. Vazza, G. Brunetti, C. Gheller
We analyze the properties of Large Scale Shocks in a cosmological volume of size 103Mpc/h simulated with the public 1.0.1 release of the ENZO code. Different methods to identify an…
A morphological comparison between giant radio halos and radio mini--halos in galaxy clusters
R. Cassano, M. Gitti, G. Brunetti
In this letter we present a morphological comparison between giant radio halos and radio mini-halos in galaxy clusters based on radio--X-ray luminosity, P_{1.4}-L_X, and radio lumi…
Shock acceleration as origin of the radio relic in A521?
S. Giacintucci, T. Venturi, G. Macario +6
We present new high sensitivity observations of the radio relic in A521 carried out with the Giant Metrewave Radio Telescope at 327 MHz and with the Very Large Array at 4.9 and 8.5…
GMRT Radio Halo Survey in galaxy clusters at z = 0.2 -- 0.4. II.The eBCS clusters and analysis of the complete sample
T. Venturi, S. Giacintucci, D. Dallacasa +4
We present the results of the GMRT cluster radio halo survey. The main purposes of our observational project are to measure which fraction of massive galaxy clusters in the redshif…
Revised statistics of radio halos and the re-acceleration model
R. Cassano, G. Brunetti, T. Venturi +4
Aims. The statistical properties of radio halos can be used to discriminate among the possible models for their origin. Therefore an unbiased and exhaustive investigation in this d…
Cosmic rays and Radio Halos in galaxy clusters : new constraints from radio observations
G. Brunetti, T. Venturi, D. Dallacasa +4
Clusters of galaxies are sites of acceleration of charged particles and sources of non-thermal radiation. We report on new constraints on the population of cosmic rays in the Intra…
Hard X-rays from Galaxy Clusters and SIMBOL-X
G. Brunetti, R. Cassano, G. Setti
Non thermal emission from galaxy clusters demonstrates the existence of relativistic particles and magnetic fields in the Intra Cluster Medium (ICM). Present instruments do not all…
An X-ray view of Pictor A radio lobes: a spatially resolved study
G. Migliori, P. Grandi, G. C. G. Palumbo +2
A spatially resolved analysis of the lobes of the radio galaxy Pictor A has been performed for the first time starting from a 50 ksec XMM-Newton observation. Magnetic field, B_{IC}…
New scaling relations in cluster radio halos and the re-acceleration model
R. Cassano, G. Brunetti, G. Setti +2
In this paper we derive new expected scaling relations for clusters with giant radio halos in the framework of the re-acceleration scenario in a simplified, but physically motivate…
Radio Lobes of Pictor A: an X-ray spatially resolved Study
G. Migliori, P. Grandi, G. G. C. Palumbo +2
A new XMM observation has made possible a detailed study of both lobes of the radio galaxy Pictor A. Their X-ray emission is of non thermal origin and due to Inverse Compton scatte…
Compressible Turbulence in Galaxy Clusters: Physics and Stochastic Particle Re-acceleration
G. Brunetti, A. Lazarian
We attempt to explain the non-thermal emission arising from galaxy clusters as a result of the re-acceleration of electrons by compressible turbulence induced by cluster mergers. I…
Low-Frequency study of two clusters of galaxies: A2744 and A2219
E. Orru', M. Murgia, L. Feretti +6
Spectral index images can be used to constraint the energy spectrum of relativistic electrons and magnetic field distribution in radio halos and relics, providing useful informatio…
Statistics of Giant Radio Halos from Electron Reacceleration Models
R. Cassano, G. Brunetti, G. Setti
The most important evidence of non-thermal phenomena in galaxy clusters comes from Giant Radio Halos (GRHs), synchrotron radio sources extended over Mpc scales, detected in a growi…
Turbulent Velocity Fields in SPH--simulated Galaxy Clusters
F. Vazza, G. Tormen, R. Cassano +2
We present a study of the turbulent velocity fields in the Intra Cluster Medium of a sample of 21 galaxy clusters simulated by the SPH--code Gadget2, using a new numerical scheme w…
Constraining B in galaxy clusters from statistics of giant radio halos
R. Cassano, G. Brunetti, G. Setti
There are several possibilities to constrain the value of the magnetic field in the ICM, the most direct ones being the combination of inverse Compton and synchrotron observations,…
The cluster relic source in A521
S. Giacintucci, T. Venturi, S. Bardelli +3
We present high sensitivity radio observations of the merging cluster A521, at a mean redsfhit z=0.247. The observations were carried out with the GMRT at 610 MHz and cover a regio…
A new XMM-Newton observation of Pictor A radio lobes confirms the non-thermal origin of the X-ray emission
G. Migliori, P. Grandi, G. G. C. Palumbo +3
X-ray emission from the eastern radio lobe of the FRII Radio Galaxy Pictor A was serendipitously discovered by a short observation of XMM-Newton in 2001. The X-ray spectrum, accumu…
Alfvenic reacceleration of relativistic particles in galaxy clusters in the presence of secondary electrons and positrons
G. Brunetti, P. Blasi
In a previous paper (Brunetti et al. 2004) we presented the first self-consistent calculations of the time-dependent coupled equations for the electrons, hadrons and Alfvén waves i…
Turbulent gas motions in galaxy cluster simulations: The role of SPH viscosity
K. Dolag, F. Vazza, G. Brunetti +1
Smoothed particle hydrodynamics (SPH) employs an artificial viscosity to properly capture hydrodynamical shock waves. In its original formulation, the resulting numerical viscosity…
Spectral properties and origin of the radio halo in A3562
S. Giacintucci, T. Venturi, G. Brunetti +6
We present a new detailed multiband study of the merging cluster A3562, in the core of the Shapley Concentration Supercluster. We analyzed new, low frequency radio data performed a…