English
Related papers

Related papers: Radiatively Efficient Magnetized Bondi Accretion

200 papers

We formulate the problem of magnetic field dissipation during the accretion phase of low-mass star formation, and we carry out the first step of an iterative solution procedure by assuming that the gas is in free-fall along radial field…

Astrophysics · Physics 2008-11-26 F. H. Shu , D. Galli , S. Lizano , M. Cai

A model for axisymmetric magnetized accretion flow is proposed. The dominant mechanism of energy dissipation is assumed to be the magnetic diffusivity due to turbulence in the accretion flow. In analogy to the advection-dominated accretion…

Astrophysics · Physics 2009-11-07 Mohsen Shadmehri

Large-scale magnetic fields are key ingredients of magnetically driven disk accretion. We study how large-scale poloidal fields evolve in accretion disks, with the primary aim of quantifying the viability of magnetic accretion mechanisms in…

Earth and Planetary Astrophysics · Physics 2015-06-17 Satoshi Okuzumi , Taku Takeuchi , Takayuki Muto

We investigate the physics of gas accretion in young stellar clusters. Accretion in clusters is a dynamic phenomenon as both the stars and the gas respond to the same gravitational potential. Accretion rates are highly non-uniform with…

Astrophysics · Physics 2011-05-05 I. A. Bonnell , M. R. Bate , C. J. Clarke , J. E. Pringle

We study the gas accretion onto a supermassive black hole (SMBH) using the 3D SPH code GADGET-3 on scales of 0.1-200 pc. First we test our code with spherically symmetric, adiabatic Bondi accretion problem. We find that our simulation can…

Cosmology and Nongalactic Astrophysics · Physics 2012-01-12 Kentaro Nagamine , Paramita Barai , Daniel Proga

We carried out 2.5-dimensional resistive magnetohydrodynamic simulations to study the effects of magnetic diffusivity on magnetically driven mass accretion and jet formation. We found that (1) when the normalized magnetic diffusivity, is…

Astrophysics · Physics 2015-06-24 T. Kuwabara , K. Shibata , R. Matsumoto

We report on the first phase of our study of slightly rotating accretion flows onto black holes. We consider inviscid accretion flows with a spherically symmetric density distribution at the outer boundary, but with spherical symmetry…

Astrophysics · Physics 2009-11-07 D. Proga , M. C. Begelman

We report on a series of numerical simulations of gas clouds with self-gravity forming sink particles, adopting an isothermal equation of state to isolate the effects of gravity from thermal physics on the resulting sink mass distributions.…

Astrophysics of Galaxies · Physics 2015-07-15 Javier Ballesteros-Paredes , Lee W. Hartmann , Nadia Perez-Goytia , Aleksandra Kuznetsova

We present nested-grid, high-resolution hydrodynamic simulations of gas and particle dynamics in the vicinity of Mars- to Earth-mass planetary embryos. The simulations extend from the surface of the embryos to a few vertical disk scale…

Earth and Planetary Astrophysics · Physics 2018-07-31 A. Popovas , Å. Nordlund , Jon P. Ramsey , Chris W. Ormel

Magnetically-arrested disks (MADs) appear when accretion flows are supplied with a sufficient amount of magnetic flux. In this work, we use results of magnetohydrodynamic simulations to set the configuration of the magnetic field and…

High Energy Astrophysical Phenomena · Physics 2020-01-31 Fu-Guo Xie , Andrzej A. Zdziarski

These Faraday rotation calculations of hot, thick accretion flows are motivated by the measured steady rotation measure (RM) of $\approx -6 \times 10^5$ rad m$^{-2}$ from Sgr A*. In our numerical simulations, the quasi-steady state…

Astrophysics · Physics 2011-02-11 Prateek Sharma , Eliot Quataert , James M. Stone

We present a 3-D ideal MHD simulation of magnetospheric accretion onto a non-rotating star. The accretion process unfolds with intricate 3-D structures driven by various mechanisms. First, the disc develops filaments at the magnetospheric…

Solar and Stellar Astrophysics · Physics 2023-12-18 Zhaohuan Zhu , James M. Stone , Nuria Calvet

Disk galaxies are in hydrostatic equilibrium along their vertical axis. The pressure allowing for this configuration consists of thermal, turbulent, magnetic and cosmic ray components. For the Milky Way(MW) the thermal pressure contributes…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Yuval Birnboim

We carry out a numerical experiment of ejecting winds in a massive colliding wind binary system, and quantifying the accretion onto the secondary star under different primary mass loss rates. We set a binary system comprising a Luminous…

Solar and Stellar Astrophysics · Physics 2022-09-21 Amit Kashi , Amir Michaelis , Yarden Kaminetsky

The recent high spatial/spectral resolution observations have enabled constraining formation mechanisms of giant planets, especially at the final stages. The current interpretation of such observations is that these planets undergo…

Earth and Planetary Astrophysics · Physics 2021-12-15 Yasuhiro Hasegawa , Kazuhiro D. Kanagawa , Neal J. Turner

We revisit Bondi accretion - steady-state, adiabatic, spherical gas flow onto a Schwarzschild black hole at rest in an asymptotically homogeneous medium - for stiff polytropic equations of state (EOSs) with adiabatic indices $\Gamma > 5/3$.…

High Energy Astrophysical Phenomena · Physics 2021-07-09 Chloe B. Richards , Thomas W. Baumgarte , Stuart L. Shapiro

We present magnetohydrodynamic numerical simulations of the late post-supernova hypercritical accretion to understand its effect on the magnetic field of the new-born neutron star. We consider as an example the case of a magnetic field loop…

High Energy Astrophysical Phenomena · Physics 2015-06-12 Cristian G. Bernal , Dany Page , William H. Lee

The problem of the late accretion phase of the evolution of an axisymmetric, isothermal magnetic disk surrounding a forming star has been formulated in a companion paper. The "central sink approximation" is used to circumvent the problem of…

Astrophysics · Physics 2009-11-10 Konstantinos Tassis , Telemachos Ch. Mouschovias

Magnetic field behaviour in a spherically-symmetric accretion flow for parameters typical of single black holes in the Galaxy is discussed. It is shown that in the majority of Galaxy volume, accretion onto single stellar-mass black holes…

Astrophysics · Physics 2009-11-10 G. M. Beskin , S. V. Karpov

It is now accepted that accretion onto classical T Tauri stars is controlled by the stellar magnetosphere, yet to date most accretion models have assumed that their magnetic fields are dipolar. By considering a simple steady state accretion…

Astrophysics · Physics 2009-11-11 S. G. Gregory , M. Jardine , I. Simpson , J. -F. Donati
‹ Prev 1 3 4 5 6 7 10 Next ›