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Related papers: Dipolar dynamos in stratified systems

200 papers

We report on simulations of mildly turbulent convection in spherical wedge geometry with varying density stratification. We vary the density contrast within the convection zone by a factor of 20 and study the influence of rotation on the…

Solar and Stellar Astrophysics · Physics 2012-04-25 P. J. Käpylä , M. J. Mantere , A. Brandenburg

The question of the origin and evolution of magnetic fields in stars possessing a radiative envelope, like the A-type stars, is still regarded as a challenge for stellar physics. Those zones are likely to be differentially rotating, which…

Solar and Stellar Astrophysics · Physics 2015-06-23 Laurène Jouve , Thomas Gastine , François Lignières

We investigate the asymptotic behaviour of a reduced {\alpha}{\Omega}-dynamo model of magnetic field generation in spiral galaxies where fluctuation in the {\alpha}-effect results in a system with state-dependent stochastic perturbations.…

Dynamical Systems · Mathematics 2016-06-15 Cónall Kelly

An update is given on the current status of solar and stellar dynamos. At present, it is still unclear why stellar cycle frequencies increase with rotation frequency in such a way that their ratio increases with stellar activity. The…

Solar and Stellar Astrophysics · Physics 2015-06-15 Axel Brandenburg

Various models of solar subsurface stratification are tested in the global EULAG-MHD solver to simulate diverse regimes of near-surface convective transport. Sub- and superadiabacity are altered at the surface of the model ($ r >…

Solar and Stellar Astrophysics · Physics 2022-11-30 Andrey M. Stejko , Gustavo Guerrero , Alexander G. Kosovichev , Piotr K. Smolarkiewicz

I study the joint effect of dynamical friction, tidal torques and cosmological constant on clusters of galaxies formation I show that within high-density environments, such as rich clusters of galaxies, both dynamical friction and tidal…

Astrophysics · Physics 2009-11-13 Antonino Del Popolo

We study the effect of strong magnetic fields, of the order of $10^{18}$-$10^{19}$ G, on the instability region of nuclear matter at subsaturation densities. Relativistic nuclear models both with constant couplings and with density…

Nuclear Theory · Physics 2009-02-18 A. Rabhi , C. Providencia , J. Da Providencia

Wind tunnel experiments were conducted to study the impact of atmospheric stratification on flow and dispersion within and over a regular array of rectangular buildings. Three stable and two convective incoming boundary layers were tested…

Atmospheric and Oceanic Physics · Physics 2020-02-10 Davide Marucci , Matteo Carpentieri

We consider the effect of stratification on systematic, large-scale flows generated in anelastic convection. We present results from three-dimensional numerical simulations of convection in a rotating plane layer in which the angle between…

Fluid Dynamics · Physics 2020-07-15 Laura K. Currie , Steven M. Tobias

Spherical solar dynamo simulations are performed. Self-consistent, fully compressible magnetohydrodynamic system with a stably stratified layer below the convective envelope is numerically solved with a newly developed simulation code based…

Solar and Stellar Astrophysics · Physics 2015-06-15 Youhei Masada , Kohei Yamada , Akira Kageyama

The amplification of magnetic fields is crucial for understanding the observed magnetization of stars and galaxies. Turbulent dynamo is the primary mechanism responsible for that but the understanding of its action in a collapsing…

Astrophysics of Galaxies · Physics 2026-04-22 Muhammed Irshad P , Pallavi Bhat , Kandaswamy Subramanian , Anvar Shukurov

We investigate the energetic ground states of a model two-phase system with 1/r^3 dipolar interactions in two dimensions. The model exhibits spontaneous formation of two kinds of periodic domain structure. A striped domain structure is…

Condensed Matter · Physics 2009-10-28 Kwok-On Ng , David Vanderbilt

Abridged. A large fraction of stars are found in binary systems. It is therefore important for our understanding of the star formation process, to investigate the fragmentation of dense molecular cores. We study the influence of the…

Astrophysics · Physics 2009-11-13 P. Hennebelle , R. Teyssier

We present the formalism and numerical results for torsional oscillations of relativistic stars endowed with a strong dipole magnetic field. We do a systematic search of parameter space by computing torsional mode frequencies for various…

Astrophysics · Physics 2008-11-26 H. Sotani , K. D. Kokkotas , N. Stergioulas

We present numerical investigations into three principal properties of the small-scale dynamo in stably stratified turbulence: the onset criterion, the growth rate, and the nature of the magnetic field anisotropy in the kinematic regime.…

Fluid Dynamics · Physics 2021-02-04 Valentin Skoutnev , Jonathan Squire , Amitava Bhattacharjee

We study the gravitationally-dominated, accretion-driven evolution of a prestellar core. In our model, as the core's density increases, it remains immersed in a constant-density environment and so it accretes from this environment,…

Astrophysics of Galaxies · Physics 2021-02-17 Gilberto C. Gómez , Enrique Vázquez-Semadeni , Aina Palau

Stably stratified layers are present in stellar interiors (radiative zones) as well as planetary interiors - recent observations and theoretical studies of the Earth's magnetic field seem to indicate the presence of a thin, stably…

Solar and Stellar Astrophysics · Physics 2019-10-10 J. Philidet , C. Gissinger , F. Lignières , L. Petitdemange

Magnetic domain structures are a fascinating area of study with interest deriving both from technological applications and fundamental scientific questions. The nature of the striped magnetic phases observed in ultra-thin films is one such…

Materials Science · Physics 2015-05-13 Tom Hosiawa , A. B. MacIsaac

We develop a mean-field model to examine the stability of a `quasi-2D suspension' of elongated particles embedded within a viscous membrane. This geometry represents several biological and synthetic settings, and we reveal mechanisms by…

Fluid Dynamics · Physics 2024-05-22 Harishankar Manikantan

We consider a bilayer of dipolar bosons in which the polarization of dipoles are perpendicular to the planes. Using accurate static structure factor $S(q)$ data from hypernetted-chain calculation for single layer dipolar bosons we construct…

Quantum Gases · Physics 2015-07-23 E. Akaturk , B. Tanatar , Saeed H. Abedinpour