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Related papers: Magnetostrophic MRI in the Earth's Outer Core

200 papers

This paper reports on 3D numerical simulations of dynamics and thermodynamics in the diffuse ISM. Our models are local, account for sheared galactic rotation, magnetic fields, and realistic cooling, and resolve scales ~1-200 pc. This…

Astrophysics · Physics 2009-11-11 Robert A. Piontek , Eve C. Ostriker

Magnet stability and reproducibility have become increasingly important as greater precision and beams with smaller dimension are required for research, medical and other purpose. The observed causes of mechanical and electrical instability…

Accelerator Physics · Physics 2011-03-09 N. Marks

Magnetorotational instability (MRI) is the most promising mechanism behind accretion in low-mass protostellar disks. Here we present the first analysis of the global structure and evolution of non-ideal MRI-driven T-Tauri disks on…

Earth and Planetary Astrophysics · Physics 2015-06-15 Russell Landry , Sarah E. Dodson-Robinson , Neal J. Turner , Greg Abram

Simulations of astrophysical disks in the shearing box that are subject to the magnetorotational instability (MRI) show that activity appears to be reduced as the magnetic Prandtl number (Pm) is lowered. On the other hand, calculations for…

Solar and Stellar Astrophysics · Physics 2015-05-18 O. M. Umurhan

Despite the importance of the magnetorotational instability (MRI) as a fundamental mechanism for angular momentum transport in magnetized accretion disks, it has yet to be demonstrated in the laboratory. A liquid sodium alpha-omega dynamo…

Astrophysics · Physics 2009-11-07 K. Noguchi , V. I. Pariev , S. A. Colgate , J. Nordhaus , H. F. Beckley

The interaction between settling of dust grains and magnetorotational instability (MRI) turbulence in protoplanetary disks is analyzed. We use a reduced system of coupled ordinary differential equations to represent the interaction between…

Earth and Planetary Astrophysics · Physics 2015-06-04 Emmanuel Jacquet , Steven Balbus

The magnetorotational instability originates from the elastic coupling of fluid elements in orbit around a gravitational well. Since inertial accelerations play a fundamental dynamical role in the process, one may expect substantial…

Astrophysics · Physics 2009-11-07 Rafael Angel Araya-Gochez

The stability of charged particle motion in a uniform magnetic field with an added spatially uniform transverse rotating magnetic field (RMF) is studied analytically. It is found that the stability diagram of a single-particle's orbit…

Plasma Physics · Physics 2024-12-13 E. Palmerduca , H. Qin , S. A. Cohen

We present long-term (~10^4 M) axisymmetric simulations of differentially rotating, magnetized neutron stars in the slow-rotation, weak magnetic field limit using a perturbative metric evolution technique. Although this approach yields…

Astrophysics · Physics 2009-11-11 Zachariah B. Etienne , Yuk Tung Liu , Stuart L. Shapiro

The questions of how strong magnetic fields can be stored in rotating stellar radiative zones without being subjected to pinch-type instabilities and how much radial mixing is produced if the fields are unstable are addressed. Linear…

Astrophysics · Physics 2009-11-13 L. L. Kitchatinov , G. Ruediger

We present an instability occurring in the inner part of disks threaded by a moderately strong vertical (poloidal) magnetic field. Its mechanism is such that a spiral density wave in the disk, driven by magnetic stresses (rather than…

Astrophysics · Physics 2007-05-23 M. Tagger , R. Pellat

The magnetohydrodynamical behavior (MHD) of accretion disks is reviewed. A detailed presentation of the fundamental MHD equations appropriate for protostellar disks is given. The combination of a weak (subthermal) magnetic field and…

Solar and Stellar Astrophysics · Physics 2009-06-05 Steven A. Balbus

In collisionless and weakly collisional plasmas, such as hot accretion flows onto compact objects, the magnetorotational instability (MRI) can differ significantly from the standard (collisional) MRI. In particular, pressure anisotropy with…

High Energy Astrophysical Phenomena · Physics 2018-02-14 Jonathan Squire , Eliot Quataert , Matthew W. Kunz

The surface layers of the Sun are strongly stratified. In the presence of turbulence with a weak mean magnetic field, a large-scale instability resulting in the formation of non-uniform magnetic structures, can be excited over the scale of…

Solar and Stellar Astrophysics · Physics 2015-12-16 Illa R. Losada , A. Brandenburg , N. Kleeorin , Dhrubaditya Mitra , I. Rogachevskii

The magnetorotational instability (MRI) may dominate outward transport of angular momentum in accretion disks, allowing material to fall onto the central object. Previous work has established that the MRI can drive a mean-field dynamo,…

Solar and Stellar Astrophysics · Physics 2015-05-27 Jeffrey S. Oishi , Mordecai-Mark Mac Low

The magnetorotational instability (MRI) drives magnetized turbulence in sufficiently ionized regions of protoplanetary disks, leading to mass accretion. The dissipation of the potential energy associated with this accretion determines the…

Earth and Planetary Astrophysics · Physics 2015-06-22 Colin P. McNally , Alexander Hubbard , Chao-Chin Yang , Mordecai-Mark Mac Low

Simulations of the magnetorotational instability (MRI) in a homogeneous shearing box have shown that the asymptotic strength of the magnetic field declines steeply with increasing resolution. Here I model the MRI driven dynamo as a large…

High Energy Astrophysical Phenomena · Physics 2011-02-11 Ethan T. Vishniac

Here it is shown how to find the interior structure of a variety of rock-and-iron planetary bodies by using the rock density and some aspects of the core density as known for the Earth and using a convection principle for the iron-rich…

Earth and Planetary Astrophysics · Physics 2018-11-26 A. Aitta

Magnetorotational instability (MRI) has a potential to generate the vigorous turbulence in protoplanetary disks, although its turbulence strength and accretion stress remains debatable because of the uncertainty of MRI with low ionization…

Earth and Planetary Astrophysics · Physics 2017-11-15 Shoji Mori , Takayuki Muranushi , Satoshi Okuzumi , Shu-ichiro Inutsuka

In dilute astrophysical plasmas, thermal conduction is primarily along magnetic field lines, and therefore highly anisotropic. As a result, the usual convective stability criterion is modified from a condition on entropy to a condition on…

Astrophysics · Physics 2008-11-26 Ian J. Parrish , James M. Stone