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Related papers: The core helium flash revisited: I. One and two-di…

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We present numerical results on three-dimensional (3D) hydrodynamic core-collapse simulations of an $11.2 M_{\odot}$ star. By comparing one-(1D) and two-dimensional(2D) results with those of 3D, we study how the increasing spacial…

High Energy Astrophysical Phenomena · Physics 2015-05-30 Tomoya Takiwaki , Kei Kotake , Yudai Suwa

The extent of mixed regions around convective zones is one of the biggest uncertainties in stellar evolution. 1D overshooting descriptions introduce a free parameter ($f_{ov}$) that is in general not well constrained from observations.…

Solar and Stellar Astrophysics · Physics 2021-03-08 Johann Higl , Ewald Mueller , Achim Weiss

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…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-24 V. Biffi , S. Borgani , G. Murante , E. Rasia , S. Planelles , G. L. Granato , C. Ragone-Figueroa , A. M. Beck , M. Gaspari , K. Dolag

Cosmological simulations still lack numerical resolution or physical processes to simulate dwarf galaxies in sufficient details. Accurate numerical simulations of individual dwarf galaxies are thus still in demand. We aim at (i) studying in…

Astrophysics of Galaxies · Physics 2015-04-20 Eduard I. Vorobyov , Simone Recchi , Gerhard Hensler

We present numerical results on two- (2D) and three-dimensional (3D) hydrodynamic core-collapse simulations of an 11.2$M_\odot$ star. By changing numerical resolutions and seed perturbations systematically, we study how the postbounce…

Solar and Stellar Astrophysics · Physics 2015-06-17 Tomoya Takiwaki , Kei Kotake , Yudai Suwa

In spite of the great effort made in the last decades to improve our understanding of stellar evolution, significant uncertainties remain due to our poor knowledge of some complex physical processes that require an empirical calibration,…

Solar and Stellar Astrophysics · Physics 2015-06-22 Alessandro Bressan , Leo Girardi , Paola Marigo , Philip Rosenfield , Jing Tang

The lithium plateau observed in halo stars has long appeared as a paradox in the general context of the lithium abundance behavior in stellar outer layers. First, the plateau is flat, second, the lithium abundance dispersion is extremely…

Astrophysics · Physics 2009-11-06 Sylvie Theado , Sylvie Vauclair

Context. Multidimensional hydrodynamic simulations of convection in stellar interiors are numerically challenging, especially for flows at low Mach numbers. Methods. We explore the benefits of using a low-Mach hydrodynamic flux solver and…

Solar and Stellar Astrophysics · Physics 2021-09-08 L. Horst , R. Hirschi , P. V. F. Edelmann , R. Andrassy , F. K. Roepke

All evolved stars with masses $M_\star\lesssim 2M_\odot$ undergo a helium(He)-core flash at the end of their first stage as a giant star. Although theoretically predicted more than 50 years ago, this core-flash phase has yet to be…

We investigate protostellar outflow evolution, gas entrainment, and star formation efficiency using radiation-hydrodynamic simulations of isolated, turbulent low-mass cores. We adopt an X-wind launching model, in which the outflow rate is…

Solar and Stellar Astrophysics · Physics 2015-06-18 S. S. R. Offner , H. G. Arce

The majority of recent hydrodynamical simulations indicate the creation of central cores in the mass profiles of low-mass halos, a process that is attributed to star formation-related baryonic feedback. Core creation is regarded as one of…

Astrophysics of Galaxies · Physics 2017-04-19 Emmanouil Papastergis , Anastasia A. Ponomareva

We construct a semi-analytical model that describes the convective core mass evolution of massive stars experiencing mass loss during the main-sequence stage. We first conduct a suite of 1D stellar evolution calculations to build insight…

Solar and Stellar Astrophysics · Physics 2024-09-04 Minori Shikauchi , Ryosuke Hirai , Ilya Mandel

We present the evolutionary models of metal-free stars in the mass range from 0.8 to 1.2 Msun with up-to-date input physics. The evolution is followed to the onset of hydrogen mixing into a convection, driven by the helium flash at red…

Astrophysics · Physics 2015-06-24 Takuma Suda , Masayuki Y. Fujimoto , Naoki Itoh

We present the first detailed three-dimensional (3D) hydrodynamic implicit large eddy simulations of turbulent convection of carbon burning in massive stars. Simulations begin with radial profiles mapped from a carbon burning shell within a…

Solar and Stellar Astrophysics · Physics 2017-08-02 Andrea Cristini , Casey Meakin , Raphael Hirschi , David Arnett , Cyril Georgy , Maxime Viallet

In the classical picture, electron-capture supernovae and the accretion-induced collapse of oxygen-neon white dwarfs (ONeWDs) undergo an oxygen deflagration phase before gravitational collapse produces a neutron star (NS). These types of…

Solar and Stellar Astrophysics · Physics 2016-09-28 Samuel Jones , Friedrich K. Roepke , Ruediger Pakmor , Ivo R. Seitenzahl , Sebastian T. Ohlmann , Philipp V. F. Edelmann

First results of numerical simulations are presented which compute the dynamical evolution of a neutron star with a mass slightly below the minimum stable mass by means of a new implicit (general relativistic) hydrodynamic code. We show…

Astrophysics · Physics 2007-05-23 K. Sumiyoshi , S. Yamada , H. Suzuki , W. Hillebrandt

(Abridged) We explore, by means of a large ensemble of SPH simulations, how the level of turbulence affects the collapse and fragmentation of a star-forming core. All our simulated cores have the same, except that we vary (a) the initial…

Astrophysics · Physics 2014-10-13 Simon P. Goodwin , Anthony P Whitworth , Derek Ward-Thompson

We study the formation and evolution of several molecules in a collapsing interstellar cloud using a reasonably large reaction network containing more then four hundred atomic and molecular species. We employ a time dependent, spherically…

Astrophysics · Physics 2009-06-30 Ankan Das , Sandip Kumar Chakrabarti , Kinsuk Acharyya , Sonali Chakrabarti

Red Clump stars have been found to be enhanced in lithium relative to stars at the tip of the Red Giant Branch (TRGB), which is unexpected in current stellar models. At the TRGB, stars undergo the helium flash, during which helium burning…

Solar and Stellar Astrophysics · Physics 2022-06-28 Adam S. Jermyn , Jim Fuller

The numerical simulation of turbulence in stars has led to a rich set of possibilities regarding stellar pulsations, asteroseismology, thermonuclear yields, and formation of neutron stars and black holes. The breaking of symmetry by…

Solar and Stellar Astrophysics · Physics 2016-10-05 W. David Arnett , Casey Meakin