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Related papers: MHD instabilities in accretion mounds - II. 3D sim…

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We present the results of three-dimensional global resistive magnetohydrodynamic (MHD) simulations of black hole accretion flows. General relativistic effects are simulated by using the pseudo-Newtonian potential. Initial state is an…

Astrophysics · Physics 2009-11-07 Mami Machida , Ryoji Matsumoto

(Abridged) We report results of three dimensional MHD simulations of global accretion disks threaded with weak vertical magnetic fields. We perform the simulations in the spherical coordinates with different temperature profiles and…

Earth and Planetary Astrophysics · Physics 2015-06-17 Takeru K. Suzuki , Shu-ichiro Inutsuka

In two previous publications$^{1,2}$, we have demonstrated that stationary rotation of magnetized plasma about a compact central object permits an enormous number of different MHD instabilities, with the well-known magneto-rotational…

Plasma Physics · Physics 2007-05-23 Hans Goedbloed , Rony Keppens

We performed the first numerical simulations of magnetorotational instability from a sub-magnetar-class seed magnetic field in core collapse supernovae. As a result of axisymmetric ideal MHD simulations, we found that the magnetic field is…

High Energy Astrophysical Phenomena · Physics 2015-06-15 Hidetomo Sawai , Shoichi Yamada , Hideyuki Suzuki

The physical modeling of the accretion disk boundary layer, the region where the disk meets the surface of the accreting star, usually relies on the assumption that angular momentum transport is opposite to the radial angular frequency…

High Energy Astrophysical Phenomena · Physics 2012-11-28 Chi-kwan Chan , Martin E. Pessah

Recent spectropolarimetric observations suggest that young low-mass stars such as classical T Tauri stars (CTTSs) possess relatively strong (~kG) magnetic field. This supports a scenario in which the final accretion onto the stellar surface…

Solar and Stellar Astrophysics · Physics 2015-06-17 Ryuichi Kurosawa , M. M. Romanova

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

We investigate the instability of purely poloidal magnetic fields in nonrotating neutron stars by means of three-dimensional general-relativistic magnetohydrodynamics simulations, extending the work presented in Ciolfi et al. (2011). Our…

Solar and Stellar Astrophysics · Physics 2015-06-05 Riccardo Ciolfi , Luciano Rezzolla

We present a detailed three dimensional magnetohydrodynamic (MHD) simulation describing the inner region of a disk accreting onto a black hole. To avoid the technical complications of general relativity, the dynamics are treated in…

Astrophysics · Physics 2009-10-31 John F. Hawley , Julian H. Krolik

Magnetorotational Instability (MRI), the instability causing turbulent transport in accretion disks, is studied in the kinetic regime. Radiatively Inefficient Accretion Flows (RIAFs), like the one around the supermassive black hole in the…

Astrophysics · Physics 2007-05-23 Prateek Sharma

Magnetohydrodynamic instabilities play an important role in accretion disks systems. Besides the well-known effects of the magnetorotational instability (MRI), the Parker-Rayleigh-Taylor instability (PRTI) also arises as an important…

High Energy Astrophysical Phenomena · Physics 2018-09-05 Luis H. S. Kadowaki , Elisabete M. de Gouveia Dal Pino , James M. Stone

We describe a three-dimensional, Godunov-type numerical magnetohydrodynamics (MHD) method designed for studying disk accretion to a rotating magnetized star in the general case where the star's rotation axis, its magnetic moment, and the…

Astrophysics · Physics 2009-11-07 A. V. Koldoba , M. M. Romanova , G. V. Ustyugova , R. V. E. Lovelace

We present global 2D and 3D simulations of self-gravitating magnetized tori. We used the 2D calculations to demonstrate that the properties of the MRI are not affected by the presence of self-gravity: MHD turbulence and enhanced angular…

It has recently been suggested that conduction-driven magnetohydrodynamic (MHD) instabilities may operate at all radii within an intracluster medium (ICM), and profoundly affect the structure of a cluster's magnetic field. Where MHD…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Tamara Bogdanovic , Christopher Reynolds , Richard Massey

We examine the effects of photon bubble instability in radiation-dominated accretion disks such as those found around black holes in active galactic nuclei and X-ray binary star systems. Two- and 3-D numerical radiation MHD calculations of…

Astrophysics · Physics 2009-11-10 N. J. Turner , O. M. Blaes , A. Socrates , M. C. Begelman , S. W. Davis

We present 3D magnetohydrodynamic (MHD) numerical simulations of the evolution of self--gravitating and weakly magnetized disks with an adiabatic equation of state. Such disks are subject to the development of both the magnetorotational and…

NASA's NICER telescope has recently provided evidence for non-dipolar magnetic field structures in rotation-powered millisecond pulsars. These stars are assumed to have gone through a prolonged accretion spin-up phase, begging the question…

High Energy Astrophysical Phenomena · Physics 2022-07-20 Pushpita Das , Oliver Porth , Anna Watts

We present three-dimensional simulations of the dynamical bar-mode instability in magnetized and differentially rotating stars in full general relativity. Our focus is on the effects that magnetic fields have on the dynamics and the onset…

General Relativity and Quantum Cosmology · Physics 2015-06-16 Luca Franci , Roberto De Pietri , Kyriaki Dionysopoulou , Luciano Rezzolla

We present the first general-relativistic resistive magnetohydrodynamics simulations of self-consistent, rotating neutron stars with mixed poloidal and toroidal magnetic fields. Specifically, we investigate the role of resistivity in the…

High Energy Astrophysical Phenomena · Physics 2026-04-28 Patrick Chi-Kit Cheong , Antonios Tsokaros , Milton Ruiz , Fabrizio Venturi , Juno Chun Lung Chan , Anson Ka Long Yip , Koji Uryu

We perform MHD simulations of a thin resistive and viscous accretion disk around a neutron star with the surface dipolar magnetic field of 10$^8$ Gauss. The system evolution is followed during the interval of 500 millisecond pulsar…

High Energy Astrophysical Phenomena · Physics 2018-02-02 M. Čemeljić , V. Parthasarathy , W. Kluźniak