English
Related papers

Related papers: Nonlinear MHD simulation of core plasma collapse e…

200 papers

We analyze the stability of a thin plasma disk which is rotating around a compact astrophysical object and is embedded in the strong magnetic field of such a source. The aim of this study is the determination of a new type of unstable…

Solar and Stellar Astrophysics · Physics 2015-06-17 Giovanni Montani , Riccardo Benini , Nakia Carlevaro , Alessio Franco

It is well-known that the cores of massive stars sustain a stellar dynamo with a complex magnetic field configuration. However, the same cannot be said for the field's strength and geometry at the convective-radiative boundary, which are…

Solar and Stellar Astrophysics · Physics 2024-12-16 Rathish P. Ratnasingam , Philipp V. F. Edelmann , Dominic M. Bowman , Tamara M. Rogers

The growth and saturation of magnetic field in conducting turbulent media with large magnetic Prandtl numbers are investigated. This regime is very common in low-density hot astrophysical plasmas. During the early (kinematic) stage, weak…

Astrophysics · Physics 2009-11-07 A. A. Schekochihin , S. C. Cowley , G. W. Hammett , J. L. Maron , J. C. McWilliams

The nonlinear evolution of the m=1 internal kink mode is studied numerically in a setting where the tokamak core plasma is surrounded by a turbulent region with low magnetic shear. As a starting point we choose configurations with three…

Plasma Physics · Physics 2007-05-23 Andreas Bierwage , Sadruddin Benkadda , Satoshi Hamaguchi , Masahiro Wakatani

Neutron stars harbour extremely strong magnetic fields within their solid outer crust. The topology of this field strongly influences the surface temperature distribution, and hence the star's observational properties. In this work, we…

High Energy Astrophysical Phenomena · Physics 2020-11-04 Davide De Grandis , Roberto Turolla , Toby S. Wood , Silvia Zane , Roberto Taverna , Konstantinos N. Gourgouliatos

Fast reconnection in magnetically dominated plasmas is widely invoked in models of dissipation in pulsar winds, gamma-ray flares in the Crab nebula, and to explain the radio nanoshots of pulsars. When current sheets evolve reaching a…

High Energy Astrophysical Phenomena · Physics 2026-02-11 Vittoria Berta , Matteo Bugli , Andrea Mignone , Giancarlo Mattia , Luca Del Zanna , Stefano Truzzi

Sawtooth-like core electron temperature crashes have been observed in W7-X experiments with electron cyclotron current drive. We present nonlinear single-fluid magnetohydrodynamic simulations of this phenomenon using the newly developed…

Plasma Physics · Physics 2023-03-17 Yao Zhou , K. Aleynikova , N. M. Ferraro

The magnetospheric plasma distribution in the vicinity of a pulsar at various inclination angles is investigated using a new relativistic, parallel 3D Particle-In-Cell (PIC) code DYMPHNA3D. DYMPHNA3D uses a superposition of the…

Astrophysics · Physics 2008-12-18 John Mc Donald , Andrew Shearer

We studied roles of a turbulent resistivity in the core-collapse of a strongly magnetized massive star, carrying out 2D-resistive-MHD simulations. The three cases with different initial strengths of magnetic field and rotation are…

High Energy Astrophysical Phenomena · Physics 2015-06-12 Hidetomo Sawai , Shoichi Yamada , Kei Kotake , Hideyuki Suzuki

We perform a three-dimensional nested-grid radiation magneto-hydrodynamics (RMHD) simulation with self-gravity to study the early phase of the low-mass star formation process from a rotating molecular cloud core to a first adiabatic core…

Solar and Stellar Astrophysics · Physics 2010-12-08 Kengo Tomida , Kohji Tomisaka , Tomoaki Matsumoto , Ken Ohsuga , Masahiro N. Machida , Kazuya Saigo

Null collapse is an implosive process whereby MHD waves focus their energy in the vicinity of a null point, forming a current sheet and initiating magnetic reconnection. We consider, for the first time, the case of collapsing 3D magnetic…

Solar and Stellar Astrophysics · Physics 2018-03-21 J. O. Thurgood , D. I. Pontin , J. A. McLaughlin

We report on the three-dimensional (3D) hydrodynamic evolution to iron core-collapse of a rapidly rotating 16 $M_{\odot}$ star. For the first time, we follow the 3D evolution of the angular momentum (AM) distribution in the iron core and…

Solar and Stellar Astrophysics · Physics 2022-01-19 C. E. Fields

The magnetorotational instability (MRI) is a fundamental mechanism determining the macroscopic dynamics of astrophysical accretion disks. In collisionless accretion flows around supermassive black holes, MRI-driven plasma turbulence…

High Energy Astrophysical Phenomena · Physics 2022-10-26 Fabio Bacchini , Lev Arzamasskiy , Vladimir Zhdankin , Gregory R. Werner , Mitchell C. Begelman , Dmitri A. Uzdensky

Magnetic fields can play a major role in the dynamics of outstanding explosions associated to violent events such as GRBs and hypernovae, since they provide a natural mechanism to harness the rotational energy of the central proto-neutron…

High Energy Astrophysical Phenomena · Physics 2021-08-04 Matteo Bugli , Jérôme Guilet , Martin Obergaulinger

The nonlinear evolution of resistive double tearing modes (DTMs) with safety factor values q=1 and q=3 is studied in a reduced cylindrical model of a tokamak plasma. We focus on cases where the resonant surfaces are a small distance apart.…

Plasma Physics · Physics 2007-05-23 Andreas Bierwage , Sadruddin Benkadda , Satoshi Hamaguchi , Masahiro Wakatani

We investigate the stability of the Hall-MHD system and determine its importance for neutron stars at their birth, when they still consist of differentially rotating plasma permeated by extremely strong magnetic fields. We solve the…

Solar and Stellar Astrophysics · Physics 2015-06-04 T. Kondic , G. Ruediger , R. Arlt

During the last decade it has become evident that the magnetorotational instability is at the heart of the enhanced angular momentum transport in weakly magnetized accretion disks around neutron stars and black holes. In this paper, we…

Astrophysics · Physics 2009-11-10 Martin E. Pessah , Dimitrios Psaltis

The nonlinear evolution of collisionless plasmas is typically a multi-scale process where the energy is injected at large, fluid scales and dissipated at small, kinetic scales. Accurately modelling the global evolution requires to take into…

Building on our previous hydrodynamic study of the angular momenta of cloud cores formed during gravitational collapse of star-forming molecular gas in our previous work, we now examine core properties assuming ideal magnetohydrodynamics…

Solar and Stellar Astrophysics · Physics 2020-04-29 Aleksandra Kuznetsova , Lee Hartmann , Fabian Heitsch

Large-scale coronal plasma evolutions can be adequately described by magnetohydrodynamics (MHD) equations. However, full multi-dimensional MHD simulations require substantial computational resources. Given the low plasma $\beta$ in the…

Solar and Stellar Astrophysics · Physics 2024-04-29 Yuhao Zhou , Xiaohong Li , Rony Keppens