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Related papers: Dynamics of Core Accretion

200 papers

Recent photometric observations of massive stars have identified a low-frequency power excess which appears as stochastic low-frequency variability in light curve observations. We present the oscillation properties of high resolution…

Solar and Stellar Astrophysics · Physics 2024-05-01 William Thompson , Falk Herwig , Paul R. Woodward , Huaqing Mao , Pavel Denissenkov , Dominic M. Bowman , Simon Blouin

Stars form in cold dense cores showing subsonic velocity dispersions. The parental molecular clouds display higher temperatures and supersonic velocity dispersions. The transition from core to cloud has been observed in velocity dispersion,…

We use a three dimensional hydrodynamical code to simulate the effect of energy injection on cooling flows in the intracluster medium. Specifically, we compare a simulation of a 10$^{15}$ $M_\odot$ cluster with radiative cooling only, with…

Astrophysics · Physics 2009-11-07 Vicent Quilis , Richard G. Bower , Michael L. Balogh

Numerical simulations of hot accretion flow have shown that the mass accretion rate decreases with decreasing radius; consequently the density profile of accretion flow becomes flatter compared to the case of a constant accretion rate. This…

High Energy Astrophysical Phenomena · Physics 2015-06-05 Feng Yuan , Maochun Wu , Defu Bu

We present the results of a numerical magnetohydrodynamic simulation that demonstrates a mechanism by which magnetic fields tap rotational energy of a stellar core and expel the envelope. Our numerical setup, designed to focus on the basic…

Astrophysics · Physics 2009-11-11 Sean Matt , Adam Frank , Eric G. Blackman , ;

A nonhydrostatic dynamical core has been developed by using the multi-moment finite volume method that ensures the rigorous numerical conservation. To represent the spherical geometry free of polar problems, the cubed-sphere grid is…

Atmospheric and Oceanic Physics · Physics 2020-04-15 Chungang Chen , Xingliang Li , Feng Xiao , Xueshun Shen

We present three-dimensional MHD simulations of rotating radiatively inefficient accretion flows onto black holes. In the simulations, we continuously inject magnetized matter into the computational domain near the outer boundary, and we…

Astrophysics · Physics 2009-11-07 Igor V. Igumenshchev , Ramesh Narayan , Marek A. Abramowicz

We perform 3D radiation hydrodynamic local shearing box simulations to study the outcome of gravitational instability (GI) in optically thick Active Galactic Nuclei (AGN) accretion disks. GI develops when the Toomre parameter QT \leq 1, and…

High Energy Astrophysical Phenomena · Physics 2023-05-24 Yi-Xian Chen , Yan-Fei Jiang , Jeremy Goodman , Eve C. Ostriker

We compute the accretion efficiency of small solids, with radii 1 cm $\le$ Rs $\le$ 10 m, on planets embedded in gaseous disks. Planets have masses 3 $\le$ Mp $\le$ 20 Earth masses (Me) and orbit within 10 AU of a solar-mass star. Disk…

Earth and Planetary Astrophysics · Physics 2024-06-06 Gennaro D'Angelo , Peter Bodenheimer

Nonspherical mass motions are a generic feature of core-collapse supernovae, and hydrodynamic instabilities play a crucial role for the explosion mechanism. First successful neutrino-driven explosions could be obtained with self-consistent,…

Solar and Stellar Astrophysics · Physics 2016-11-23 H. -Thomas Janka , Tobias Melson , Alexander Summa

We explore the thermodynamic and global structural properties of a local patch of an accretion disk whose parameters were chosen so that radiation pressure and gas pressure would be comparable in magnitude. Heating, radiative transport, and…

Astrophysics · Physics 2009-06-23 Julian H. Krolik , Shigenobu Hirose , Omer Blaes

Understanding the growth of the cores of giant planets is a difficult problem. Recently, Lambrechts and Johansen (2012; LJ12) proposed a new model in which the cores grow by the accretion of pebble-size objects, as the latter drift towards…

Earth and Planetary Astrophysics · Physics 2015-06-11 Alessandro Morbidelli , David Nesvorny

Circumplanetary disks (CPDs) may be essential to the formation of planets, regulating their spin and accretion evolution. We perform a series of 3D hydrodynamics simulations in both the isothermal and adiabatic limits to systematically…

Earth and Planetary Astrophysics · Physics 2020-01-08 Jeffrey Fung , Zhaohuan Zhu , Eugene Chiang

We have performed fully 3D simulations of the collapse of molecular cloud cores which obey the logatropic equation of state. By following the collapse of these cores from states of near hydrodynamic equilibrium, we are able to produce…

Astrophysics · Physics 2007-05-23 M. A. Reid , R. E. Pudritz , J. Wadsley

We perform direct numerical simulations of the tidal encounter of a rotating planet on a highly eccentric or parabolic orbit about a central star formulated as an initial value problem. This approach enables us to extend previous work of…

Solar and Stellar Astrophysics · Physics 2015-05-19 J. C. B. Papaloizou , P. B. Ivanov

The growth process of proto-planets can be sped-up by accreting a large number of solid, pebble-sized objects that are still present in the protoplanetary disc. It is still an open question on how efficient this process works in realistic…

Earth and Planetary Astrophysics · Physics 2018-08-29 Giovanni Picogna , Moritz H. R. Stoll , Wilhelm Kley

We present here results of numerical simulations of the formation and early evolution of rocky planets through pebble accretion, with an with an emphasis on hydrogen envelope longevity and the composition of the outgassed atmosphere. We…

Earth and Planetary Astrophysics · Physics 2024-11-13 Piia Maria Tomberg , Anders Johansen

Using a hydrodynamic adaptive mesh refinement code, we simulate the growth and evolution of a galaxy, which could potentially host a supermassive black hole, within a cosmological volume. Reaching a dynamical range in excess of 10 million,…

Astrophysics · Physics 2008-11-26 Robyn Levine , Nickolay Y. Gnedin , Andrew J. S. Hamilton , Andrey V. Kravtsov

Using molecular dynamics simulations we investigate the thermodynamic of particles interacting with a continuous and a discrete versions of a core-softened (CS) intermolecular potential composed by a repulsive shoulder. Dynamic and…

Statistical Mechanics · Physics 2007-09-12 Alan Barros de Oliveira , Paulo A. Netz , Marcia C. Barbosa

In this paper we study the gravitational collapse of a molecular hydrogen gas cloud composed of a core plus a gas envelope surrounding the core. We numerically simulate the collapse of four cloud models to take a glimpse to the time…

Solar and Stellar Astrophysics · Physics 2013-08-21 Guillermo Arreaga-Garcia , Julio Saucedo Morales