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Related papers: Some improvements to the spherical collapse model

200 papers

The influence of the shear stress and angular momentum on the nonlinear spherical collapse model is discussed in the framework of the Einstein-de Sitter (EdS) and $\Lambda$CDM models. By assuming that the vacuum component is not clustering…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-11 Antonino Del Popolo , Francesco Pace , J. A. S. Lima

It has recently been suggested that in the presence of driven turbulence discs may be much less stable against gravitational collapse than their non turbulent analogs, due to stochastic density fluctuations in turbulent flows. This mode of…

Earth and Planetary Astrophysics · Physics 2018-01-31 Ken Rice , Sergei Nayakshin

The splashback radius is one popular method of constraining the size of galaxy clusters, often measured through the logarithmic derivative of the galaxy number density profile. However, measuring the splashback radius through the galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-12 Talia M. O'Shea , Josh Borrow , Stephanie O'Neil , Mark Vogelsberger

Star formation is intimately linked to the dynamical evolution of molecular clouds. Turbulent fragmentation determines where and when protostellar cores form, and how they contract and grow in mass via accretion from the surrounding cloud…

Astrophysics · Physics 2007-05-23 Ralf Klessen

The radii of young (<100 Myr) star clusters correlate only weakly with their masses. This shallow relation has been used to argue that impulsive tidal perturbations, or `shocks', by passing giant molecular clouds (GMCs) preferentially…

Astrophysics of Galaxies · Physics 2016-09-19 Mark Gieles , Florent Renaud

Dynamical evolution of stellar mass distribution in star clusters is analysed by considering simultaneously the effects of dynamical friction, stochastic heating and the gravitational potential due to mass distribution in the clusters. A…

Astrophysics · Physics 2007-05-23 S. Chatterjee , Brijesh Kumar , Ram Sagar

We study the evolution of disc galaxies in group environments under the effect of both the global tidal field and close-encounters between galaxies, using controlled N-body simulations of isolated mergers. We find that close-range…

Astrophysics of Galaxies · Physics 2015-06-19 Álvaro Villalobos , Gabriella De Lucia , Giuseppe Murante

With the aim of distinguishing between possible physical mechanisms acting on galaxies when they fall into clusters, we study the properties of the gas and the stars in a sample of 422 emission-line galaxies from EDisCS in different…

The amplification of magnetic fields is crucial for understanding the observed magnetization of stars and galaxies. Turbulent dynamo is the primary mechanism responsible for that but the understanding of its action in a collapsing…

Astrophysics of Galaxies · Physics 2026-04-22 Muhammed Irshad P , Pallavi Bhat , Kandaswamy Subramanian , Anvar Shukurov

(ABBREVIATED) Understanding the formation of stars in galaxies is central to much of modern astrophysics. In this review the relation between interstellar turbulence and star formation is discussed. Supersonic turbulence can provide support…

Astrophysics · Physics 2009-09-29 Ralf S. Klessen

The dynamic evolution of galactic bars in standard $\Lambda$CDM models is dominated by angular momentum loss to the dark matter haloes via dynamical friction. Traditional approximations to dynamical friction are formulated using the…

Astrophysics of Galaxies · Physics 2022-04-29 Rimpei Chiba , Ralph Schönrich

We study the evolution of star clusters in the Galactic tidal field starting from their birth in molecular clumps. Our model clusters form according to the local-density-driven cluster formation model in which the stellar density profile is…

Astrophysics of Galaxies · Physics 2020-03-18 Bekdaulet Shukirgaliyev , Genevieve Parmentier , Peter Berczik , Andreas Just

A new theory for determining the mass function of cosmic structures is presented. It relies on a realistic treatment of collapse dynamics. Gravitational collapse is analyzed in the Lagrangian perturbative framework. Lagrangian perturbations…

Astrophysics · Physics 2015-06-24 Pierluigi Monaco

The effect of background dynamics of the universe on formation of large scale structures in the framework of Modified Newtonian Dynamics (MOND) is investigated. A spherical collapse model is used for modeling the formation of the…

General Relativity and Quantum Cosmology · Physics 2015-05-28 M. Malekjani , H. Haghi , D. M. Z Jassur

It has been known for some time that rotating bars in galaxies slow due to dynamical friction against the halo. However, recent attempts to use this process to place constraints on the dark matter density in galaxies and possibly also to…

Astrophysics · Physics 2016-08-30 J. A. Sellwood

We analyze the effects induced by the bulk viscosity on the dynamics associated to the extreme gravitational collapse. Aim of the work is to investigate whether the presence of viscous corrections to the evolution of a collapsing gas cloud…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Nakia Carlevaro , Giovanni Montani

We extend a previous work by Reischke et al., 2016 by studying the effects of tidal shear on clustering dark energy models within the framework of the extended spherical collapse model and using the Zel'dovich approximation. As in previous…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-18 Francesco Pace , Robert Reischke , Sven Meyer , Björn Malte Schäfer

We examine the changes in the properties of galactic bulges and discs with environment for a volume-limited sample of 12500 nearby galaxies from SDSS. We focus on galaxies with classical bulges. Classical bulges seem to have the same…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 C. N. Lackner , J. E. Gunn

The turbulent motion within molecular clouds is a key factor controlling star formation. Turbulence supports molecular cloud cores from evolving to gravitational collapse and hence sets a lower bound on the size of molecular cloud cores in…

Solar and Stellar Astrophysics · Physics 2015-06-23 Yang Gao , Haitao Xu , Chung K. Law

We present the results of a series of numerical simulations aimed to study the evolution of a disc galaxy within the global tidal field of a group environment. Both the disc galaxy and the group are modelled as multi-component,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Álvaro Villalobos , Gabriella De Lucia , Stefano Borgani , Giuseppe Murante