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Related papers: The Impact of Non-Equipartition on Cosmological Pa…

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(abridged) We have studied the effects of electron-ion non-equipartition in the outer regions of relaxed clusters for a wide range of masses in the \LambdaCDM cosmology using one-dimensional hydrodynamic simulations. The effects of the…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-14 Ka-Wah Wong , Craig L. Sarazin

Use of the Sunyaev-Zeldovich effect as a precise cosmological probe necessitates a realistic assessment of all possible contributions to Comptonization of the cosmic microwave background in clusters of galaxies. We have calculated the…

Astrophysics · Physics 2015-06-24 Meir Shimon , Yoel Rephaeli

Sensitive surveys of the Cosmic Microwave Background will detect thousands of galaxy clusters via the Sunyaev-Zel'dovich (SZ) effect. Two SZ observables, the central or maximum and integrated Comptonization parameters y_max and Y, relate in…

Astrophysics · Physics 2009-11-13 Daniel R. Wik , Craig L. Sarazin , Paul M. Ricker , Scott W. Randall

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

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 utility of large Sunyaev Zel'dovich (SZ) surveys for determining cosmological parameters from cluster abundances is limited by the theoretical uncertainties in the integrated SZ-flux-to-mass relation, Y-M. We explore how non-thermal…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 N. Battaglia , J. R. Bond , C. Pfrommer , J. L. Sievers

We investigate how strongly and at what scales the Sunyaev- Zel'dovich effect reflects the shifting balance between the two processes that compete for governing the density and the thermodynamic state of the hot intra-cluster medium…

Astrophysics · Physics 2009-11-06 A. Cavaliere , N. Menci

The Sunyaev-Zel'dovich effect (SZE) observable-mass (Y-M) scaling relation is a promising technique for obtaining mass estimates for large samples of galaxy clusters and holds a key to studying the nature of dark matter and dark energy.…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-30 Liang Yu , Kaylea Nelson , Daisuke Nagai

Scaling relations among galaxy cluster observables, which will become available in large future samples of galaxy clusters, could be used to constrain not only cluster structure, but also cosmology. We study the utility of this approach,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Cien Shang , Zoltan Haiman , Licia Verde

A recent stacking analysis of Planck HFI data of galaxy clusters (Hurier 2016) allowed to derive the cluster temperatures by using the relativistic corrections to the Sunyaev-Zel'dovich effect (SZE). However, the temperatures of…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-28 P. Marchegiani , S. Colafrancesco

Forthcoming large galaxy cluster surveys will yield tight constraints on cosmological models. It has been shown that in an idealized survey, containing > 10,000 clusters, statistical errors on dark energy and other cosmological parameters…

Astrophysics · Physics 2008-11-26 Joshua D. Younger , Zoltan Haiman , Greg L. Bryan , Sheng Wang

The densities in the outer regions of clusters of galaxies are very low, and the collisional timescales are very long. As a result, heavy elements will be under-ionized after they have passed through the accretion shock. We have studied…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Ka-Wah Wong , Craig L. Sarazin , Li Ji

We investigate empirical scaling relations between the thermal Sunyaev-Zeldovich effect (SZE) and cluster mass in simulated clusters of galaxies. The simulated clusters have been compiled from four different samples that differ only in…

Astrophysics · Physics 2009-11-10 Patrick M. Motl , Eric J. Hallman , Jack O. Burns , Michael L. Norman

Observations of the X-ray band wavelength reveal an evident ellipticity of many galaxy clusters atmospheres. The modeling of the intracluster gas with an ellipsoidal $\beta$-model leads to different estimates for the total gravitational…

Astrophysics · Physics 2009-09-29 Ph. Jetzer , P. Koch , R. Piffaretti , D. Puy , S. Schindler

We propose a new method to model cluster scaling relations in modified gravity. Using a suite of non-radiative hydrodynamical simulations, we show that the scaling relations of cumulative gas quantities, such as the Sunyaev Zel'dovich…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-15 Jian-hua He , Baojiu Li

X-ray observations of galaxy cluster merger shocks can be used to constrain nonthermal processes in the intracluster medium (ICM). The presence of nonthermal pressure components in the ICM, as well as the shock acceleration of particles and…

Astrophysics · Physics 2011-02-11 Ehud Nakar , Milos Milosavljevic , Daisuke Nagai

We present thermal Sunyaev-Zel'dovich effect (SZE) measurements for 42 galaxy clusters observed at 150 GHz with the APEX-SZ experiment. For each cluster, we model the pressure profile and calculate the integrated Comptonization $Y$ to…

We critically analyze the measurement of galaxy cluster gas masses, which is central to cosmological studies that rely on the galaxy cluster gas mass fraction. Using synthetic observations of numerically simulated clusters viewed through…

Astrophysics · Physics 2009-11-11 Eric J. Hallman , Patrick M. Motl , Jack O. Burns , Michael L. Norman

Using N-body/hydrodynamic simulations, the influence of non-equipartition processes on the thermal and dynamical properties of cosmological baryonic gas is investigated. We focus on a possible departure from equilibrium between electrons,…

Astrophysics · Physics 2009-11-10 S. Courty , J. -M. Alimi

Uncertainty in the mass-observable scaling relations is currently the limiting factor for galaxy cluster based cosmology. Weak gravitational lensing can provide a direct mass calibration and reduce the mass uncertainty. We present new…

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