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Related papers: Disk accretion onto a magnetized star

200 papers

In this paper I analyze the process of formation of thin current structures in the magnetosphere of a conducting accretion disk in response to the field-line twisting brought about by the rotation of the disk relative to the central star. I…

Astrophysics · Physics 2009-11-07 Dmitri A. Uzdensky

Accretion disks are ubiquitous in the universe and it is generally accepted that magnetic fields play a pivotal role in accretion-disk physics. The spin history of millisecond pulsars, which are usually classified as magnetized neutron…

Solar and Stellar Astrophysics · Physics 2013-12-16 Luca Naso , John Miller , Wlodek Kluzniak

Many types of stars have strong magnetic fields that can dynamically influence the flow of circumstellar matter. In stars with accretion disks, the stellar magnetic field can truncate the inner disk and determine the paths that matter can…

Solar and Stellar Astrophysics · Physics 2016-05-18 M. M. Romanova , S. P. Owocki

When an accreting star is close to rotational equilibrium between the dipole component of the stellar magnetic field and the accretion disk, the star's rotation rate is roughly of the order of the Keplerean rotation rate at the inner…

High Energy Astrophysical Phenomena · Physics 2015-06-05 M. Ali Alpar

Our understanding of the dynamical processes which control the structure and evolution of the interaction region between an accretion disk and the central star is reviewed. If the central star is unmagnetized, this interaction is in the…

Astrophysics · Physics 2009-10-30 James M. Stone

The origin of disks surrounding young stars has direct implications for our understanding of the formation of planetary systems. In the interstellar clouds from which star form, angular momentum is regulated by magnetic fields, preventing…

Astrophysics · Physics 2007-05-23 Michiel R. Hogerheijde

The inner 0.1 AU around accreting T Tauri stars hold clues to many physical processes that characterize the early evolution of solar-type stars. The accretion-ejection connection takes place at least in part in this compact magnetized…

Astrophysics · Physics 2007-05-23 J. Bouvier , S. H. P. Alencar , T. J. Harries , C. M. Johns-Krull , M. M. Romanova

We present the first results of a global axisymmetric simulation of accretion onto rotating magnetized stars from a turbulent, MRI-driven disk. The angular momentum is transported outward by the magnetic stress of the turbulent flow with a…

Solar and Stellar Astrophysics · Physics 2015-05-27 Marina M. Romanova , Galina V. Ustyugova , Alexander V. Koldoba , Richard V. E. Lovelace

We show that a large-scale, weak magnetic field threading a turbulent accretion disk tends to be advected inward, contrary to previous suggestions that it will be stopped by outward diffusion. The efficient inward transport is a consequence…

Astrophysics · Physics 2009-11-13 David M. Rothstein , Richard V. E. Lovelace

Study of observed spin evolution of long-period X-ray pulsars challenges quasi-spherical and Keplerian disk accretion scenarios. It suggests that the magnetospheric radius of the neutron stars is substantially smaller than Alfven radius and…

High Energy Astrophysical Phenomena · Physics 2015-06-18 Nazar Ikhsanov , Nina Beskrovnaya , Yury Likh

The origin of the spins of giant planets is an open question in astrophysics. As planets and stars accrete from discs, if the specific angular momentum accreted corresponds to that of a Keplerian orbit at the surface of the object, it is…

Earth and Planetary Astrophysics · Physics 2021-09-29 Alexander J. Dittmann

We assess the modification of angular momentum transport in various configurations of star-disk accreting systems based on numerical simulations with different parameters. We quantify the torques exerted on a star by the various components…

Solar and Stellar Astrophysics · Physics 2023-11-01 M. Čemeljić , A. S. Brun

We investigate spherical accretion to a rotating magnetized star in the "propeller" regime using axisymmetric resistive magnetohydrodynamic simulations. The regime is predicted to occur if the magnetospheric radius is larger than the…

Astrophysics · Physics 2007-05-23 O. D. Toropina , M. M. Romanova , R. V. E. Lovelace

We report on the first global three-dimensional (3D) MHD simulations of disk accretion onto a rotating magnetized star through the Rayleigh-Taylor instability. The star has a dipole field misaligned relative to the rotation axis by a small…

Astrophysics · Physics 2018-01-17 Marina M. Romanova , Akshay K. Kulkarni , Richard V. E. Lovelace

Strong magnetization makes the disks surrounding young stellar objects rotate at rates that are too sub-Keplerian to enable the thermal launching of disk winds from their surfaces unless the rate of gas diffusion across field lines is…

Astrophysics · Physics 2009-11-13 Frank H. Shu , Susana Lizano , Daniele Galli , Mike J. Cai , Subhanjoy Mohanty

Structure of a quasi-stationary stellar cluster is modelled assuming that it is embedded in the gravitational field of a super-massive black hole. Gradual orbital decay of stellar trajectories is caused by the dissipative interaction with…

Astrophysics · Physics 2007-05-23 L. Subr , V. Karas , J. -M. Hure

In this paper, we present the complete structure of a quasi-Keplerian thin accretion disk with an internal dynamo around a magnetized neutron star. We assume a full quasi-Keplerian disk with the azimuthal velocity deviating from the…

High Energy Astrophysical Phenomena · Physics 2019-03-20 Isaac Habumugisha , Edward Jurua , Solomon B. Tessema , Anguma K. Simon

I show in this paper that two types of magnetic torques can appear in the interaction between an accretion disc and a magnetic accretor. There is the well-known torque resulting from the difference in angular velocity between the accretion…

Astrophysics · Physics 2009-10-30 Ulf Torkelsson

We investigate two-temperature accretion flows onto strongly magnetized compact stars. Matter is accreted in the form of an accretion disc upto the disc radius ($r_{\rm d}$), where, the magnetic pressure exceeds both the gas and ram…

High Energy Astrophysical Phenomena · Physics 2023-04-19 Shilpa Sarkar , Kuldeep Singh , Indranil Chattopadhyay , Philippe Laurent

We present the results of a global, three-dimensional magnetohydrodynamics simulation of an accretion disk with a rotating, weakly magnetized central star. The disk is threaded by a weak, large-scale poloidal magnetic field, and the central…

Solar and Stellar Astrophysics · Physics 2019-02-07 Shinsuke Takasao , Kengo Tomida , Kazunari Iwasaki , Takeru K. Suzuki