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Related papers: Entropy generation in merging galaxy clusters

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We present a new approach to understanding star-to-star helium abundance variations within globular clusters. We begin with detailed radiation hydrodynamics simulations of cluster formation within giant molecular clouds, and investigate the…

Astrophysics of Galaxies · Physics 2020-03-18 Alison Sills

Galaxy clusters grow by gas accretion, mostly from mergers of substructures, which release powerful shock waves into cosmic plasmas and convert a fraction of kinetic energy into thermal energy, amplification of magnetic fields and into the…

High Energy Astrophysical Phenomena · Physics 2019-03-11 A. M. Bykov , F. Vazza , J. A. Kropotina , K. P. Levenfish , F. B. S. Paerels

We use semi-analytic models and cosmological merger trees to provide the initial conditions for multi-merger numerical hydrodynamic simulations, and exploit these simulations to explore the effect of galaxy interaction and merging on star…

Astrophysics of Galaxies · Physics 2015-08-06 Wouter Karman , Andrea V. Maccio , Rahul Kannan , Benjamin P. Moster , Rachel S. Somerville

The self-enrichment of massive star clusters by p-processed elements is shown to increase significantly with increasing gas density as a result of enhanced star formation rates and stellar scatterings compared to the lifetime of a massive…

Astrophysics of Galaxies · Physics 2017-02-15 Bruce G. Elmegreen

Merging of galaxy clusters are some of the most energetic events in the Universe, and they provide a unique environment to study galaxy evolution. We use a sample of 84 merging and relaxed SPT galaxy clusters candidates, observed with the…

We analyse the spatial distribution of halo merger sites using four numerical simulations with high time resolution of structure growth in a Lambda-CDM cosmology. We find no evidence for any large-scale relative bias between mergers and…

Astrophysics · Physics 2008-11-26 Will J. Percival , Douglas Scott , John A. Peacock , James S. Dunlop

Clusters of galaxies are the largest organized structures in the Universe. They are important cosmological probes, since they are large enough to contain a fair sample of the materials in the Universe, but small enough to have achieved…

Astrophysics · Physics 2009-11-07 Craig L. Sarazin

Major astrophysical questions related to the formation and evolution of structures, and more specifically of galaxy groups and clusters, will still be open in the coming decade and beyond: what is the interplay of galaxy, supermassive black…

Numerical simulations of clusters of galaxies provide a unique way to follow the dynamics of these systems. The models reveal many characteristics of the merging process of subclusters: shock structure and strength, temperature distribution…

Astrophysics · Physics 2007-05-23 Sabine Schindler

Understanding heating processes in galaxy clusters is essential for predicting the regulation of radiative cooling and star formation, and for clarifying the mechanisms underlying active galactic nucleus (AGN) feedback in cool-core…

High Energy Astrophysical Phenomena · Physics 2026-03-31 Moun Meenakshi , Rainer Weinberger , Christoph Pfrommer , Thomas Berlok

We present a new model for the creation of cool cores in rich galaxy clusters within a LambdaCDM cosmological framework using the results from high spatial dynamic range, adaptive mesh hydro/N-body simulations. It is proposed that cores of…

Astrophysics · Physics 2007-05-23 J. O. Burns , P. M. Motl , M. L. Norman , G. L. Bryan

The nonthermal radiation observed from a handfull of clusters of Galaxies is the proof that particle acceleration occurs in the intracluster medium. It is often believed that shock surfaces associated with either mergers of clusters of…

Astrophysics · Physics 2007-05-23 Pasquale Blasi , Stefano Gabici

We review the theory of the formation of galaxy clusters and discuss their role as cosmological probes. We begin with the standard cosmological framework where we discuss the origin of the CDM matter power spectrum and the growth of density…

Astrophysics · Physics 2007-05-23 Michael L. Norman

A significant fraction of galaxy clusters show central cooling times of less than 1 Gyr and associated central cluster entropies below $30\,\mathrm{keV}\,\mathrm{cm}^2$. We provide a straight forward explanation for these low central…

Astrophysics of Galaxies · Physics 2026-02-11 Rainer Weinberger , Christoph Pfrommer

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

We investigated the numerical and physical reasons leading to a flat distribution of low gas entropy in the core region of galaxy clusters, as commonly found in grid cosmological simulations. To this end, we run a set of 30 high resolution…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 F. Vazza

We compare the nonthermal emission from clusters of galaxies undergoing minor mergers (``accreting'' clusters) and major mergers (``merging'' clusters). For accreting clusters, the radial distribution of the nonthermal emission in the…

Astrophysics · Physics 2009-11-07 Yutaka Fujita , Craig L. Sarazin

We simulate star formation and star cluster assembly inside a molecular cloud with parameters we derive directly from observations of the Aquila Rift. We model the evolution of stars and gas together while resolving close encounters between…

Astrophysics of Galaxies · Physics 2026-05-12 Jeremy Karam , Michiko S. Fujii , Rachel Friesen , Alison Sills

Central regions of superclusters are the ideal places where to study cluster merging phenomena: in fact the accretion activity is enhanced, as predicted by the cosmological simulations. In this paper I review the case-study of the Shapley…

Astrophysics · Physics 2009-11-10 S. Bardelli

We present cosmological simulations of galaxy clusters, with focus on the cluster outskirts. We show that large-scale cosmic accretion and mergers produce significant internal gas motions and inhomogeneous gas distribution ("clumpiness") in…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-10 Daisuke Nagai