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Gravothermal oscillations occur in several models for the post-collapse evolution of rich star clusters. This paper reviews the main literature, and presents some new N-body results which appear to exhibit this phenomenon.

Astrophysics · Physics 2007-05-23 Douglas C. Heggie

A number of globular clusters appear to have undergone core collapse, in the sense that their predicted collapse time is much shorter than their current age. Simulations using gas models and Fokker-Planck approximation have shown that the…

Astrophysics · Physics 2009-10-28 Junichiro Makino

In this paper, gravothermal oscillations are investigated in multi-component star clusters which have power law initial mass functions (IMF). For the power law IMFs, the minimum masses ($m_{min}$) were fixed and three different maximum…

Astrophysics of Galaxies · Physics 2015-06-05 Philip G. Breen , Douglas C. Heggie

We study the dynamical evolution of globular clusters using our H\'enon-type Monte Carlo code for stellar dynamics including all relevant physics such as two-body relaxation, single and binary stellar evolution, Galactic tidal stripping,…

Astrophysics of Galaxies · Physics 2015-06-05 Sourav Chatterjee , Stefan Umbreit , John M. Fregeau , Frederic A. Rasio

We report on the results of a direct N-body simulation of a star cluster that started with N = 200 000, comprising 195 000 single stars and 5 000 primordial binaries. The code used for the simulation includes stellar evolution, binary…

Astrophysics of Galaxies · Physics 2015-06-11 Jarrod R. Hurley , Michael M. Shara

Stars form by gravoturbulent fragmentation of interstellar gas clouds. The supersonic turbulence ubiquitously observed in Galactic molecular gas generates strong density fluctuations with gravity taking over in the densest and most massive…

Two-component (normal and degenerate stars) models are the simplest realization of clusters with a mass spectrum because high mass stars evolve quickly into degenerates, while low mass stars remain on the main-sequence for the age of the…

Astrophysics · Physics 2015-06-24 Sungsoo S. Kim , Hyung Mok Lee , Jeremy Goodman

Due to the gas rich environments of early circumstellar disks, the gravitational collapse of cool, dense regions of the disk form fragments largely composed of gas. During formation, disk fragments may attain increased metallicities as they…

Earth and Planetary Astrophysics · Physics 2019-08-26 Hans Baehr , Hubert Klahr

Self-gravitating galactic halos composed of self-interacting dark matter exhibit the formation of a highly dense core at the galactic center--a gravothermal collapse. Analytic models to describe this evolution have been developed and…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-29 Marc Kamionkowski , Kris Sigurdson

We present numerical investigations into the formation of massive stars from centrally condensed turbulent cores. The results of five hydrodynamical simulations are described, following the collapse of the core, fragmentation and the…

Astrophysics · Physics 2009-11-10 Clare L. Dobbs , Ian A. Bonnell , Paul C. Clark

Star clusters with multi-mass components dynamically evolve faster than those modeled with equal-mass components. Using a series of direct $N$-body simulations, we investigate the dynamical evolution of star clusters with mass functions,…

Astrophysics of Galaxies · Physics 2014-06-09 M. S. Fujii , S. Portegies Zwart

This paper describes the numerical evolution of an $N$-body system with a slight ``temperature inversion''; i.e. the maximum velocity dispersion occurs not at the centre but further out. Fluid models predict that the core of such a system…

Astrophysics · Physics 2015-06-24 Douglas C. Heggie , Shogo Inagaki , Stephen L. W. McMillan

Subsequent to Paper I, the evolution and fragmentation of a rotating magnetized cloud are studied with use of three-dimensional MHD nested-grid simulations. After the isothermal runaway collapse, an adiabatic gas forms a protostellar first…

Astrophysics · Physics 2009-11-13 Masahiro N Machida , Tomoaki Matsumoto , Tomoyuki Hanawa , Kohji Tomisaka

We investigate numerically and semi-analytically the collapse of low-mass, rotating prestellar cores. Initially, the cores are in approximate equilibrium with low rotation (the initial ratio of thermal to gravitational energy is $\alpha_0…

Astrophysics · Physics 2009-11-10 P. Hennebelle , A. Whitworth , S. Cha , S. Goodwin

The isothermal gravitational collapse and fragmentation of a region within a molecular cloud and the subsequent formation of a protostellar cluster is investigated numerically. The clump mass spectrum which forms during the fragmentation…

Astrophysics · Physics 2009-10-30 Ralf S. Klessen , Andreas Burkert , Matthew R. Bate

The formation process of high-mass stars (>8M$_\odot$) is poorly constrained, particularly, the effects of clump fragmentation creating multiple systems and the mechanism of mass accretion onto the cores. We study the fragmentation of dense…

The evolution of spherical single-mass star clusters driven by two-body relaxation was followed beyond core collapse by numerically solving the orbit-averaged Fokker-Planck equation in energy--angular momentum space. The heating effect by…

Astrophysics · Physics 2015-06-24 Koji Takahashi

It has been shown that a discontinuity in the derivatives of the sound speed at the edge of the convective regions inside a star gives rise to a characteristic oscillatory signal in the frequencies of stellar oscillations. This oscillatory…

Astrophysics · Physics 2009-11-07 Anwesh Mazumdar , H. M. Antia

We study the stability of filaments in equilibrium between gravity and internal as well as external pressure using the grid based AMR-code RAMSES. A homogeneous, straight cylinder below a critical line mass is marginally stable. However, if…

Solar and Stellar Astrophysics · Physics 2017-01-18 Matthias Gritschneder , Stefan Heigl , Andreas Burkert

Theory and simulations are used to study collisionless relaxation of a gravitational $N$-body system. It is shown that when the initial one particle distribution function satisfies the virial condition -- potential energy is minus twice the…

Statistical Mechanics · Physics 2008-08-25 Yan Levin , Renato Pakter , Felipe B. Rizzato
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