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Related papers: Heat conduction in X-ray clusters: Spitzer over 3

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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 have calculated lower limits for the global effective thermal conductivity in a sample of 165 Abell clusters. We assumed that cluster X-ray luminosity is compensated by a conductive heat flux which we then compare with an upper limit to…

Astrophysics · Physics 2007-05-23 Mikhail V. Medvedev , Adrian L. Melott , Chris Miller , Donald Horner

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

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 argue that it is currently impossible to simulate X-ray clusters using correct equations, because even the MHD description is not applicable. But since fluid simulations actually reproduce observations quite well, one may try to improve…

Astrophysics · Physics 2007-05-23 A. Gruzinov

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

I study non-radiative cooling of X-ray emitting gas via heat conduction along magnetic field lines inside magnetic flux loops in cooling flow clusters of galaxies. I find that such heat conduction can reduce the fraction of energy radiated…

Astrophysics · Physics 2009-11-10 Noam Soker

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

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

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

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

We study the possibility that a large fraction of the gas at temperatures of \~10^7 K in cooling flow clusters cools by heat conduction to lower temperatures, rather than by radiative cooling. We argue that this process, when incorporated…

Astrophysics · Physics 2009-11-10 Noam Soker , Elizabeth L. Blanton , Craig L. Sarazin

(abridged) Uninhibited radiative cooling in clusters of galaxies would lead to excessive mass accretion rates contrary to observations. One of the key proposals to offset radiative energy losses is thermal conduction from outer, hotter…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 M. Ruszkowski , S. Peng Oh

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

We investigate field-line separation in strong MHD turbulence using direct numerical simulations. We find that in the static-magnetic-field approximation the thermal conductivity in galaxy clusters is reduced by a factor of about 50…

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

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

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

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…

Simulations of galaxy clusters have a difficult time reproducing the radial gas-property gradients and red central galaxies observed to exist in the cores of galaxy clusters. Thermal conduction has been suggested as a mechanism that can…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Britton D. Smith , Brian W. O'Shea , G. Mark Voit , David Ventimiglia , Samuel W. Skillman

ROSAT observations indicate that approximately half of all nearby groups of galaxies contain spatially extended X-ray emission. The radial extent of the X-ray emission is typically 50-500 kpc or approximately 10-50% of the virial radius of…

Astrophysics · Physics 2009-10-31 John S. Mulchaey
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