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Related papers: Probing the dynamical state of galaxy clusters

200 papers

The strong lensing events that are observed in compact clusters of galaxies can, both statistically and individually, return important clues about the structural properties of the most massive structures in the Universe. Substantial work is…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 C. Fedeli , M. Meneghetti , S. Gottloeber , G. Yepes

The cosmological parameters prefered by the cosmic microwave background (CMB) primary anisotropies predict many more galaxy clusters than those that have been detected via the thermal Sunyaev-Zeldovich (tSZ) effect. This tension has…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-28 G. Hurier , R. E. Angulo

Machine learning (ML) techniques, in particular supervised regression algorithms, are a promising new way to use multiple observables to predict a cluster's mass or other key features. To investigate this approach we use the \textsc{MACSIS}…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-16 Thomas J. Armitage , Scott T. Kay , David J. Barnes

We introduce an analytic model of the diffuse intergalactic medium in galaxy clusters based on a polytropic equation of state for the gas in hydrostatic equilibrium with the cluster gravitational potential. This model is directly applicable…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 G. Esra Bulbul , Nicole Hasler , Massimiliano Bonamente , Marshall Joy

We use high resolution simulations to study the formation and distribution of galaxies within a cluster which forms hierarchically. We follow both dark matter and baryonic gas which is subject to thermal pressure, shocks and radiative…

Astrophysics · Physics 2009-09-25 C. S. Frenk , A. E. Evrard , S. D. M. White , FJ Summers

Recent hydrostatic X-ray studies of the hot interstellar medium (ISM) in early-type galaxies underestimate the gravitating mass as compared to stellar dynamics, implying modest, but significant deviations from exact hydrostatic equilibrium.…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Philip J. Humphrey , David A. Buote , Fabrizio Brighenti , Karl Gebhardt , William G. Mathews

Clusters of galaxies are powerful probes with which to study cosmology and astrophysics. However, for many applications an accurate measurement of a cluster's mass is essential. A systematic underestimate of hydrostatic masses from X-ray…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-21 Crispin H. A. Logan , Ben J. Maughan , Antonaldo Diaferio , Ryan T. Duffy , Margaret J. Geller , Kenneth Rines , Jubee Sohn

Modified Newtonian Dynamics (MOND) was originally proposed to model galaxy rotation curves without dark matter. However, MOND presents difficulties in explaining the Radial Acceleration Relation (RAR) observed in galaxy clusters, and…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-24 Robert Monjo

Galaxy clusters provide us with important information about the cosmology of our universe. Observations of the X-ray radiation or of the SZ effect allow us to measure the density and temperature of the hot intergalactic medium between the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Diana Juncher , Steen H. Hansen , Andrea V. Macciò

The process of galaxy cluster formation likely leaves an imprint on the properties of its individual member galaxies. Understanding this process is essential for uncovering the evolutionary connections between galaxies and cosmic…

In this work, we present results for the photometric and clustering properties of galaxies that arise in a LambdaCDM hydrodynamical simulation of the local universe. The present-day distribution of matter was constructed to match the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 S. E. Nuza , K. Dolag , A. Saro

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…

Based on the earlier work of Gunn and McCrea we model the formation of globular clusters in merging galaxies. Neutral hydrogen observations of dwarf irregular galaxies as well as more luminous systems are used to provide the key parameters…

Astrophysics · Physics 2011-02-11 F. D. A. Hartwick

We present a novel approach for a combined analysis of X-ray and gravitational lensing data and apply this technique to the merging galaxy cluster MACS J0416.1$-$2403. The method exploits the information on the intracluster gas distribution…

Astrophysics of Galaxies · Physics 2017-08-04 M. Bonamigo , C. Grillo , S. Ettori , G. B. Caminha , P. Rosati , A. Mercurio , M. Annunziatella , I. Balestra , M. Lombardi

Clusters of galaxies, the largest collapsed structures in the Universe, are located at the intersection of extended filaments of baryons and dark matter. Cosmological accretion onto clusters through large scale filaments adds material at…

We review and discuss information on the mass distribution of galaxy clusters obtained from gravitational lensing.

Astrophysics · Physics 2009-10-22 Matthias Bartelmann , Ramesh Narayan

Weak gravitational lensing is a powerful probe for constraining cosmological parameters, but its success relies on accurate shear measurements. In this paper, we use image simulations to investigate how a joint analysis of high-resolution…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-22 Shiyang Zhang , Shun-Sheng Li , Henk Hoekstra

We propose a new cluster deprojection algorithm for recovering cluster structure along the line of sight (los) based on the Richardson-Lucy (RL) algorithm, which recovers a nonnegative theoretical distribution from a given projection. To…

Astrophysics · Physics 2007-05-23 Katrin Reblinsky , Matthias Bartelmann

We develop a method for reconstructing the two-dimensional, projected gravitational potential of galaxy clusters from observed line-of-sight velocity dispersions of cluster galaxies. It is the third of an intended series of papers aiming at…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Eleonora Sarli , Sven Meyer , Massimo Meneghetti , Sara Konrad , Charles L. Majer , Matthias Bartelmann

Using hydrodynamical simulations, we study how well the underlying gravitational potential of a galaxy cluster can be modelled dynamically with different types of tracers. In order to segregate different systematics and the effects of…

Astrophysics of Galaxies · Physics 2021-06-30 Qingyang Li , Jiaxin Han , Wenting Wang , Weiguang Cui , Zhaozhou Li , Xiaohu Yang