相关论文: Galaxy cluster hydrostatic masses using Tolman-Opp…
The location of a galaxy cluster's centroid is typically derived from observations of the galactic and/or gas component of the cluster, but these typically deviate from the true centre. This can produce bias when observations are combined…
We study the uncertainty in galaxy cluster mass estimates derived from X-ray data assuming hydrostatic equilibrium (HE) for the intra cluster gas. Using a Monte-Carlo procedure we generate a general class of mass models allowing very…
This is the third in a series of papers studying the astrophysics and cosmology of massive, dynamically relaxed galaxy clusters. Our sample comprises 40 clusters identified as being dynamically relaxed and hot (i.e., massive) in Papers I…
We present galaxy velocity dispersions and dynamical mass estimates for 44 galaxy clusters selected via the Sunyaev-Zel'dovich (SZ) effect by the Atacama Cosmology Telescope. Dynamical masses for 18 clusters are reported here for the first…
We determine the distance to 38 clusters of galaxies in the redshift range 0.14 < z < 0.89 using X-ray data from Chandra and Sunyaev-Zeldovich Effect data from the Owens Valley Radio Observatory and the Berkeley-Illinois-Maryland…
We apply the 1+1+2 covariant approach to describe a general static and spherically symmetric relativistic stellar object which contains two interacting fluids. We then use the 1+1+2 equations to derive the corresponding…
The growth of structure in the Universe is tightly correlated with the cosmological parameters. Galaxy clusters as tracers of the large scale structure are the ideal objects to witness this evolution. The X-ray bright, hot gas in the…
We present a comprehensive joint analysis of two distinct methodologies for measuring the mass of galaxy clusters: hydrostatic measurements and caustic techniques. We show that by including cluster-specific assumptions obtained from…
In the context of linear $f(\mathcal{R},T)=\mathcal{R}+\chi T$ gravity, where $\mathcal{R}$ is the Ricci scalar, $T$ is the trace of the energy-momentum tensor, and $\chi$ is a dimensionless parameter, we have obtained exact analytical and…
In this paper we investigate the level of hydrostatic equilibrium (HE) in the intra-cluster medium of simulated galaxy clusters, extracted from state-of-the-art cosmological hydrodynamical simulations performed with the…
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…
Recently, the covariant formulation of the Tolman-Oppenheimer-Volkoff (TOV) equations for studying the equilibrium structure of a spherically symmetric compact star in the presence of the pressure anisotropy in the interior of a star was…
The exploitation of clusters of galaxies as cosmological probes relies on accurate measurements of their total gravitating mass. X-ray observations provide a powerful means of probing the total mass distribution in galaxy clusters, but…
We re-examine the constraints which can be robustly obtained from the observed temperature function of X-ray cluster of galaxies. The cluster mass function has been thoroughly studied in simulations and analytically, but a direct simulation…
This paper introduces an accelerated power series solution for Tolman-Oppenheimer-Volkoff (TOV) equation, which represents the relativistic polytropic fluid spheres. We constructed a recurrence relation for the series coefficients in the…
We present a covariant description of non-vacuum static spherically symmetric spacetimes in $f(R)$ gravity applying the (1+1+2) covariant formalism. The propagation equations are then used to derive a covariant and dimensionless form of the…
We test the reliability of mass determination in clusters of galaxies by X-ray observations. The true mass in cluster models is compared to the mass derived by the X-ray emission and X-ray temperature of a model assuming hydrostatic…
The thermal properties of hydrodynamical simulations of galaxy clusters are usually compared to observations by relying on the emission-weighted temperature T_ew, instead of on the spectroscopic X-ray temperature T_spec, which is obtained…
Galaxy and galaxy clusters exhibit tight robust physical scaling relations between baryons and system dynamics. One such phenomenon is mass discrepancy with two leading solution spaces occupied by LCDM and MOND. Here, we propose an…
In this paper, we present a new hydrostatic equilibrium equation related to dilaton gravity. We consider a spherical symmetric metric to obtain the hydrostatic equilibrium equation of stars in $4$-dimensions, and generalize TOV equation to…