English
Related papers

Related papers: Nonlinear magnetic buoyancy instability and turbul…

200 papers

We investigate the cosmic ray driven dynamo in the interstellar medium of irregular galaxy. The observations (Chyzy et al. 2000, 2003) show that the magnetic field in irregular galaxies is present and its value reaches the same level as in…

High Energy Astrophysical Phenomena · Physics 2009-11-13 Hubert Siejkowski , Marian Soida , Katarzyna Otmianowska-Mazur , Michał Hanasz , Dominik Bomans

The magneto-rotational instability (MRI) is the most likely mechanism for transportation of angular momentum and dissipation of energy within hot, ionized accretion discs. This instability is produced through the interactions of a…

High Energy Astrophysical Phenomena · Physics 2021-12-08 Oscar M. Pimentel , P. Chris Fragile , F. D. Lora-Clavijo , Bridget Ierace , Deepika Bollimpalli

Magnetic fields are an important component of the interstellar medium (ISM) and exhibit strongly varying field strengths and a non-trivial correlation with the gas density. Its dynamical impact varies between individual regions of the ISM…

Astrophysics of Galaxies · Physics 2021-08-20 Philipp Girichidis

We study a new type of large-scale instability, which arises in obliquely rotating stratified electroconductive fluid with an external uniform magnetic field and a small-scale external force having zero helicity. This force gives rise to…

Fluid Dynamics · Physics 2018-07-06 M. I. Kopp , K. N. Kulik , A. V. Tur , V. V. Yanovsky

We study the properties of the turbulence driven by the magnetorotational instability (MRI) in a stratified shearing box with outflow boundary conditions and an equation of state determined by self-consistent dissipation and radiation…

High Energy Astrophysical Phenomena · Physics 2014-11-20 Ji-Ming Shi , Julian H. Krolik , Shigenobu Hirose

Astrophysical disks with localized radial structure, such as protoplanetary disks containing dead zones or gaps due to disk-planet interaction, may be subject to the non-axisymmetric Rossby wave instability (RWI) that lead to…

Earth and Planetary Astrophysics · Physics 2015-06-11 Min-Kai Lin

We investigate the stability to nonaxisymmetric perturbations of an accretion disc in which a poloidal magnetic field provides part of the radial support against gravity. Interchange instability due to radial gradients in the magnetic field…

Astrophysics · Physics 2015-06-24 H. C. Spruit , R. Stehle , J. C. B. Papaloizou

We present results of three-dimensional nonlinear MHD simulations of a large-scale magnetic field and its evolution inside a barred galaxy with the back reaction of the magnetic field on the gas. The model does not consider the dynamo…

Astrophysics of Galaxies · Physics 2015-05-13 B. Kulesza-Zydzik , K. Kulpa-Dybel , K. Otmianowska-Mazur , G. Kowal , M. Soida

The magnetic fields of spiral galaxies are so strong that they cannot be primordial. Their typical values are over one billion times higher than any value predicted for the early Universe. Explaining this immense growth and incorporating it…

Astrophysics of Galaxies · Physics 2020-09-30 Evangelia Ntormousi , Konstantinos Tassis , Fabio Del Sordo , Francesca Fragkoudi , Rüdiger Pakmor

Magnetic fields in upper main-sequence stars, white dwarfs, and neutron stars are known to persist for timescales comparable to their lifetimes. From a theoretical perspective this is problematic, as it can be shown that simple magnetic…

Solar and Stellar Astrophysics · Physics 2015-06-12 Taner Akgün , Andreas Reisenegger , Alpha Mastrano , Pablo Marchant

Convection in massive main sequence stars generates large scale magnetic fields in their cores which persists as they evolve up the red giant branch. The remnants of these fields may take the form of the Prendergast magnetic field, a…

Solar and Stellar Astrophysics · Physics 2022-10-12 Emma Kaufman , Daniel Lecoanet , Evan H. Anders , Benjamin P. Brown , Geoffrey M. Vasil , Jeffrey S. Oishi , Keaton J. Burns

Magnetohydrodynamic (MHD) instabilities can play an important role in the dynamics of the pulsar magnetosphere and can be responsible for the formation of various structures. We consider the instability caused by a gradient of the magnetic…

Solar and Stellar Astrophysics · Physics 2014-03-05 Vadim Urpin

Gravitational instability (GI) features in several aspects of protostellar disk evolution, most notably in angular momentum transport, fragmentation, and the outbursts exemplified by FU Ori and EX Lupi systems. The outer regions of…

Earth and Planetary Astrophysics · Physics 2016-06-24 A. Riols , H. Latter

The effect of the Hall term on the evolution of the magnetorotational instability (MRI) in weakly ionized accretion disks is investigated using local axisymmetric simulations. First, we show that the Hall term has important effects on the…

Astrophysics · Physics 2009-11-07 Takayoshi Sano , James M. Stone

In the presence of strong density stratification, turbulence can lead to a large-scale instability of a horizontal magnetic field if its strength is in a suitable range (within a few percent of the turbulent equipartition value). This…

Solar and Stellar Astrophysics · Physics 2014-04-28 Sarah Jabbari , Axel Brandenburg , Nathan Kleeorin , Dhrubaditya Mitra , Igor Rogachevskii

In weakly collisional extragalactic plasmas such as the intracluster medium, viscous stress and the rate of change of the magnetic-field strength are proportional to the local pressure anisotropy, so subject to constraints imposed by the…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-26 Federico Mogavero , Alexander A. Schekochihin

The evolution of magnetic fields is studied using simulations of forced helical turbulence with strong imposed shear. After some initial exponential growth, the magnetic field develops a large scale travelling wave pattern. The resulting…

Astrophysics · Physics 2009-10-31 Axel Brandenburg , Alberto Bigazzi , Kandaswamy Subramanian

(Abridged) The rotational evolution of isolated neutron stars is dominated by the magnetic field anchored to the solid crust of the star. Assuming that the core field evolves on much longer timescales, the crustal field evolves mainly…

Solar and Stellar Astrophysics · Physics 2013-06-11 Jose A. Pons , Daniele Vigano , Ulrich Geppert

The importance of the interstellar magnetic field is studied in relation to the evolutions of superbubbles with a three-dimensional (3D) numerical magnetohydrodynamical (MHD) simulation. A superbubble is a large supernova remnant driven by…

Astrophysics · Physics 2009-10-30 Kohji Tomisaka

The vertical phase-space spirals in the Milky Way are clear evidence of disequilibrium. However, they are challenging to study because phase mixing signals evolve under the influence of many different dynamical processes and can be driven…