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Related papers: Are Large X-ray Clusters at Thermal Equilibrium ?

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We present simulations of the formation and evolution of galaxy clusters in the Cold Dark Matter cosmogony. Clusters with a wide range of mass were selected from previous N-body models, and were resimulated at higher resolution using a…

Astrophysics · Physics 2015-06-24 Julio F. Navarro , Carlos S. Frenk , Simon D. M. White

The analysis of X-ray and Sunyaev-Zel\'dovich measurements of the intracluster medium (ICM) assumes that electrons are in thermal equilibrium with ions in the plasma. However, electron-ion equilibration timescales can be comparable to the…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-20 Camille Avestruz , Daisuke Nagai , Erwin T. Lau , Kaylea Nelson

The virialization shock around an X-ray cluster primarily heats the ions, since they carry most of the kinetic energy of the infalling gas. Subsequently, the ions share their thermal energy with the electrons through Coulomb collisions. We…

Astrophysics · Physics 2009-10-30 David Fox , Abraham Loeb

We present high-resolution cosmological hydrodynamic simulations of three galaxy clusters employing a two-temperature model for the intracluster medium. We show that electron temperatures in cluster outskirts are significantly lower than…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-11 Douglas H. Rudd , Daisuke Nagai

Analyses of cosmological hydrodynamic simulations of galaxy clusters suggest that X-ray masses can be underestimated by 10% to 30%. The largest bias originates by both violation of hydrostatic equilibrium and an additional temperature bias…

We calculate X-ray properties of present-day galaxy clusters from hydrodynamical cosmological simulations of the LCDM cosmology and compare these with recent X-ray observations. Results from three simulations are presented, each of which…

Astrophysics · Physics 2009-11-07 Orrarujee Muanwong , Peter A. Thomas , Scott T. Kay , Frazer R. Pearce

Thermal X-ray spectra of clusters of galaxies and other sources are commonly calculated assuming Maxwellian electron distributions. There are situations where this approximation is not valid, for instance near interfaces of hot and cold gas…

High Energy Astrophysical Phenomena · Physics 2015-05-13 J. S. Kaastra , A. M. Bykov , N. Werner

A fraction of the thermal protons in the outer envelope of an X-ray cluster have velocities that exceed the local escape speed from the cluster gravitational potential. The Coulomb mean-free-path of these protons is larger than the virial…

Astrophysics · Physics 2010-10-27 Abraham Loeb

Results from a large sample of hydrodynamical/N-body simulations of galaxy clusters in a LCDM cosmology are used to simulate cluster X-ray observations as expected from Chandra observations. The physical modeling of the gas includes…

Astrophysics · Physics 2009-11-11 R. Valdarnini

We present results on the X-ray properties of clusters and groups of galaxies, extracted from a large hydrodynamical simulation. We used the GADGET code to simulate a LambdaCDM model within a box of 192 Mpc/h on a side, with 480^3 dark…

We investigate a non-equilibrium ionization state and an electron-ion two-temperature structure of the intracluster medium in the merging galaxy cluster, 1E0657-56 (the Bullet cluster), using a series of N-body and hydrodynamic simulations.…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Takuya Akahori , Kohji Yoshikawa

Theoretical studies of the physical processes guiding the formation and evolution of galaxies and galaxy clusters in the X-ray are mainly based on the results of numerical hydrodynamical N-body simulations, which in turn are often directly…

Astrophysics · Physics 2015-06-24 P. Mazzotta , E. Rasia , L. Moscardini , G. Tormen

To study the mass distribution of galaxy clusters up to their Virial radius, CL0016+16 seems to be a good candidate,since it is a bright massive cluster, previously considered as being dynamically relaxed. Using XMM-Newton observations of…

Astrophysics · Physics 2009-11-13 L. Solovyeva , S. Anokhin , J. L. Sauvageot , R. Teyssier , D. Neumann

We present an observational analysis of numerical simulations of galaxy cluster mergers. We identify several observational signatures of recent merger activity, and quantitatively assess the uncertainty introduced into cluster mass…

Astrophysics · Physics 2009-10-28 Kurt Roettiger , Jack O. Burns , Chris Loken

We present the first self-consistently computed results on the evolution of X-ray properties of galaxy clusters in a Cold + Hot Dark Matter (CHDM) model. We have performed a hydrodynamic plus N-body simulation for the COBE-compatible CHDM…

Astrophysics · Physics 2009-10-22 Greg L. Bryan , Anatoly Klypin , Chris Loken , Michael L. Norman , Jack O. Burns

We have simulated the formation of an X-ray cluster in a cold dark matter universe using 12 different codes. The codes span the range of numerical techniques and implementations currently in use, including SPH and grid methods with fixed,…

We present results from a study of the X-ray cluster population that forms within the CLEF cosmological hydrodynamics simulation, a large N-body/SPH simulation of the Lambda CDM cosmology with radiative cooling, star formation and feedback.…

A recent and unexpected discrepancy between \textit{ab initio} simulations and the interpretation of a laser shock experiment on aluminum, probed by X-ray Thomson scattering (XRTS), is addressed. The ion-ion structure factor deduced from…

Plasma Physics · Physics 2020-11-19 J. Clerouin , P. Arnault , G. Robert , C. Ticknor , J. Kress , L. Collins

We examine the relationship between the mass and x-ray gas temperature of galaxy clusters using data drawn from the literature. Simple theoretical arguments suggest that the mass of a cluster is related to the x-ray temperature as $M…

Astrophysics · Physics 2009-10-31 Donald J. Horner , Richard F. Mushotzky , Caleb A. Scharf

Recent high resolution observations by the {\it Chandra} X-ray satellite revealed various substructures in hot X-ray emitting plasmas in cluster of galaxies. For example, {\it Chandra} revealed the existence of sharp discontinuities in the…

Astrophysics · Physics 2009-11-11 Naoki Asai , Naoya Fukuda , Ryoji Matsumoto
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