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Related papers: Limits on thermal conduction in galaxy clusters

200 papers

Conduction may play an important role in reducing cooling flows in galaxy clusters. We analyse a sample of sixteen objects using Chandra data and find that a balance between conduction and cooling can exist in the hotter clusters (T > 5…

Astrophysics · Physics 2009-09-17 L. M. Voigt , A. C. Fabian

On the basis of the universal gas fraction in clusters of galaxies, we estimate that the effective thermal conductivity required to balance radiative cooling in the cores, where the gas temperature is 3-10keV, is about one tenth of the…

Astrophysics · Physics 2009-11-07 A. C. Fabian , L. M. Voigt , R. G. Morris

We use Chandra data to derive a detailed gas temperature map of the nearby, hot, merging galaxy cluster A754. Combined with the X-ray and optical images, the map reveals a more complex merger geometry than previously thought, possibly…

We estimate the thermal conductivity of a weakly collisional magnetized plasma with chaotic magnetic field fluctuations. When the fluctuation spectrum extends over two or more decades in wave-vector, we find that thermal conduction is very…

Astrophysics · Physics 2009-11-07 Ramesh Narayan , Mikhail V. Medvedev

We show that X-ray clusters would have cooled substantially over a Hubble time by transport of heat from their hot interior to the their envelope, if the heat conductivity had not been heavily suppressed relative to the Spitzer value due to…

Astrophysics · Physics 2015-06-24 Abraham Loeb

We present a simple model of hot gas in galaxy clusters, assuming hydrostatic equilibrium and energy balance between radiative cooling and thermal conduction. For five clusters, A1795, A1835, A2199, A2390 and RXJ1347.5-1145, the model gives…

Astrophysics · Physics 2011-06-21 Nadia L. Zakamska , Ramesh Narayan

Chandra and XMM-Newton observations have confirmed the presence of large temperature gradients within the cores of many relaxed clusters of galaxies. Here we investigate whether thermal conduction operating over those gradients can supply…

Astrophysics · Physics 2009-11-07 L. M. Voigt , R. W. Schmidt , A. C. Fabian , S. W. Allen , R. M. Johnstone

We study the formation of clusters of galaxies using high-resolution hydrodynamic cosmological simulations that include the effect of thermal conduction with an effective isotropic conductivity of 1/3 the classical Spitzer value. We find…

Astrophysics · Physics 2009-11-10 K. Dolag , M. Jubelgas , V. Springel , S. Borgani , E. Rasia

Effective heat conduction in a random variable magnetic field should be equal to one third of the Spitzer's value. Recent observations indicate that this heat conduction is sufficient to account for the bremsstrahlung in cooling X-ray…

Astrophysics · Physics 2007-05-23 Andrei Gruzinov

Thermal conduction has been suggested as a possible mechanism by which sufficient energy is supplied to the central regions of galaxy clusters to balance the effect of radiative cooling. Here we present the results of a simulated,…

Astrophysics · Physics 2009-11-13 Edward C. D. Pope , Georgi Pavlovski , Christian R. Kaiser , Hans Fangohr

Galaxy clusters host a large reservoir of diffuse plasma with radially-varying temperature profiles. The efficiency of thermal conduction in the intracluster medium (ICM) is complicated by the existence of turbulence and magnetic fields,…

High Energy Astrophysical Phenomena · Physics 2018-08-29 Xiang-Er Fang , Fulai Guo , Ye-Fei Yuan , Guobin Mou

Galaxy clusters are filled with hot, diffuse X-ray emitting plasma, with a stochastically tangled magnetic field whose energy is close to equipartition with the energy of the turbulent motions \cite{zweibel1997, Vacca}. In the cluster…

Cluster cooling flow models that include both thermal conduction and AGN heating have lower overall mass cooling rates and simultaneously sustain density and temperature profiles similar to those observed with no ad hoc mass dropout. To…

Astrophysics · Physics 2009-11-07 Fabrizio Brighenti , William G. Mathews

The results of hydrodynamic simulations of the Virgo and Perseus clusters suggest that thermal conduction is not responsible for the observed temperature and density profiles. As a result it seems that thermal conduction occurs at a much…

Astrophysics · Physics 2007-05-23 Edward Pope , Christian Kaiser , Georgi Pavlovski , Hans Fangohr

In this Letter, we use the recent Chandra observation of A2142 reported by Markevitch et al. to put constraints on thermal conduction in the intracluster plasma. We show that the observed sharp temperature gradient requires that classical…

Astrophysics · Physics 2009-10-31 S. Ettori , A. C. Fabian

We investigate field-line separation in strong MHD turbulence analytically and with direct numerical simulations. We find that in the static-magnetic-field approximation the thermal conductivity in galaxy clusters is reduced by a factor of…

Astrophysics · Physics 2009-11-07 Benjamin D. G. Chandran , Jason L. Maron

The cluster of galaxies Abell 2146 is undergoing a major merger and is an ideal cluster to study ICM physics, as it has a simple geometry with the merger axis in the plane of the sky, its distance allows us to resolve features across the…

Thermal conductivity coefficient $\kappa$ measures the ability of a material to conduct a heat current. In particular, $\kappa$ is an important property that often dictates the usefulness of a material over a wide range of environmental…

Soft Condensed Matter · Physics 2024-10-23 Debashish Mukherji

Thermal conduction in tangled magnetic fields is reduced because heat conducting electrons must travel along the field lines longer distances between hot and cold regions of space than if there were no fields. We consider the case when the…

Astrophysics · Physics 2009-10-31 Leonid Malyshkin

There has been extensive recent progress in X-ray observations of clusters of galaxies with the analysis of the entire ASCA database and recent new results from Beppo-SAX, Chandra, and XMM-Newton. The temperature profiles of most clusters…

Astrophysics · Physics 2007-05-23 Richard F. Mushotzky
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