English
Related papers

Related papers: Dynamo saturation in direct simulations of the mul…

200 papers

The evolution of large-scale magnetic fields in disk galaxies is investigated numerically. The gasdynamical simulations in a disk perturbed by spiral or bar potential are incorporated into the kinematic calculations of induction equations…

Astrophysics · Physics 2007-05-23 K. Otmianowska-Mazur , M. Chiba

Star-forming dwarf galaxies can be seen as the local proxies of the high-redshift building blocks of more massive galaxies according to the current paradigm of the hierarchical galaxy formation. They are low-mass objects, and therefore…

Astrophysics of Galaxies · Physics 2015-06-18 H. Siejkowski , K. Otmianowska-Mazur , M. Soida , D. J. Bomans , M. Hanasz

In this paper we further advance the study of magnetic field amplification in the interstellar medium that was started in Balsara et al (2004, Paper I). We show that the flux growth rate is comparable to the rate of magnetic energy growth…

Astrophysics · Physics 2009-11-10 D. S. Balsara , J. S. Kim

While the saturated magnetic energy is independent of viscosity in dynamo experiments, it remains viscosity-dependent in state-of-the-art 3D direct numerical simulations (DNS). Extrapolating such viscous scaling-laws to realistic parameter…

Fluid Dynamics · Physics 2017-12-20 Kannabiran Seshasayanan , Basile Gallet , Alexandros Alexakis

Mean field dynamo theory is a leading candidate to explain the observed large scale magnetic fields of galaxies and stars. However, controversy arises over the extent of premature quenching by the backreaction of the growing field. We…

Astrophysics · Physics 2009-10-31 Eric G. Blackman , George B. Field

The role of magnetic fields in the multi-phase interstellar medium (ISM) is explored using magnetohydrodynamic (MHD) simulations that include energy injection by supernova (SN) explosions and allow for dynamo action. Apart from providing…

Astrophysics of Galaxies · Physics 2018-10-03 A. Shukurov , C. C. Evirgen , A. Fletcher , P. J. Bushby , F. A. Gent

The origin of strong magnetic fields in the Universe can be explained by amplifying weak seed fields via turbulent motions on small spatial scales and subsequently transporting the magnetic energy to larger scales. This process is known as…

The mechanism of large-scale dynamos in rigidly rotating stratified convection is explored by direct numerical simulations (DNS) in Cartesian geometry. A mean-field dynamo model is also constructed using turbulent velocity profiles…

Solar and Stellar Astrophysics · Physics 2015-06-22 Youhei Masada , Takayoshi Sano

The fractal shape and multi-component nature of the interstellar medium together with its vast range of dynamical scales provides one of the great challenges in theoretical and numerical astrophysics. Here we will review recent progress in…

Astrophysics of Galaxies · Physics 2015-05-27 Oliver Gressel , Detlef Elstner , Günther Rüdiger

Understanding large scale magnetic field growth in turbulent plasmas in the magnetohydrodynamic limit is a goal of magnetic dynamo theory. In particular, assessing how well large scale helical field growth and saturation in simulations…

Plasma Physics · Physics 2015-06-15 Kiwan Park , Eric G. Blackman , Kandaswamy Subramanian

We use high-resolution MHD simulations of isolated disk galaxies to investigate the co-evolution of magnetic fields with a self-regulated, star-forming interstellar medium (ISM). The simulations are conducted using the Ramses AMR code on…

Astrophysics of Galaxies · Physics 2024-06-05 Hector Robinson , James Wadsley

We study the influence of initial conditions on the magnetic field amplification during the collapse of a magnetised gas cloud. We focus on the dependence of the growth and saturation level of the dynamo generated field on the turbulent…

Solar and Stellar Astrophysics · Physics 2015-06-04 Sharanya Sur , Christoph Federrath , Dominik R. G. Schleicher , Robi Banerjee , Ralf S. Klessen

We conduct a series of magnetohydrodynamical (MHD) simulations of magnetized interstellar medium (ISM) disturbed by exploding stars. Each star deposits a randomly oriented, dipolar magnetic field into ISM. The simulations are performed in a…

Astrophysics · Physics 2011-11-10 K. Kowalik , M. Hanasz

Solar, stellar and galactic large-scale magnetic fields are originated due to a combined action of non-uniform (differential) rotation and helical motions of plasma via mean-field dynamos. Usually, nonlinear mean-field dynamo theories take…

Solar and Stellar Astrophysics · Physics 2024-04-19 I. Rogachevskii , N. Kleeorin

The formation and evolution of a wide class of astrophysical objects is governed by turbulent, magnetized accretion disks. Understanding their secular dynamics is of primary importance. Apart from enabling mass accretion via the transport…

High Energy Astrophysical Phenomena · Physics 2015-09-16 Oliver Gressel , Martin E. Pessah

Observations have suggested substantial departures from pressure equilibrium in the interstellar medium (ISM) in the plane of the Galaxy, even on scales under 50 pc. Nevertheless, multi-phase models of the ISM assume at least locally…

Astrophysics · Physics 2009-11-10 Mordecai-Mark Mac Low , Dinshaw S. Balsara , Jongsoo Kim , Miguel A. Avillez

The interstellar medium (ISM) is permeated by magnetic fields that affect gas dynamics and star formation. These fields correlate with supernova (SN)-driven turbulence, but whether the scaling is universal across galaxy properties, ISM…

Astrophysics of Galaxies · Physics 2026-03-31 Davide Belfiori , Sergio Martin-Alvarez , Enrique Lopez-Rodriguez , Rosita Paladino

We present three-dimensional magneto-hydrodynamical simulations of the self-gravitating interstellar medium (ISM) in a periodic (256 pc)$^3$ box with a mean number density of 0.5 cm$^{-3}$. At a fixed supernova rate we investigate the…

Convection is one of the most important mixing processes in stellar interiors. Hydrodynamic mass entrainment can bring fresh fuel from neighboring stable layers into a convection zone, modifying the structure and evolution of the star.…

Solar and Stellar Astrophysics · Physics 2023-11-29 G. Leidi , R. Andrassy , J. Higl , P. V. F. Edelmann , F. K. Röpke

We present kinematic simulations of a galactic dynamo model based on the large scale differential rotation and the small scale helical fluctuations due to supernova explosions. We report for the first time direct numerical simulations of…

Astrophysics of Galaxies · Physics 2009-11-13 Christophe Gissinger , Sebastien Fromang , Emmanuel Dormy