相关论文: Nonlinear Galactic Dynamos and the Magnetic Pitch …

Large-scale magnetic fields in stars and galaxies are thought to arise by mean-field dynamo action due to the combined influence of both helical turbulence and shear. Those systems are also highly conducting and the turbulence therein leads…

The measured rotation velocity profiles of mature spiral galaxies are successfully described with a gravitational model consisting of a thin axisymmetric disk of finte radius. The disk is assumed uniformly thin but with variable radial mass…

The existence of a weak galactic magnetic field has been repeatedly confirmed by observational data. The origin of this field has not as yet been explained in a fully satisfactory way and represents one of the main challenges of the…

The popular outer gap model of magnetospheric emission from pulsars has been widely applied to explain the properties observed in $\gamma$-rays. However, its quantitative predictions rely on a number of approximations and assumptions that…

The origin of large-scale magnetic fields, detected in some low-mass (dwarf and irregular) galaxies via polarised synchrotron emission and Faraday rotation, remained unexplained for a long time. We suggest that mean-field dynamo can be…

Observations have suggested that some low-mass stars have larger radii than predicted by 1-D structure models. Some theoretical models have invoked very strong interior magnetic fields (of order 1 MG or more) as a possible cause of such…

Additional physics beyond standard hydrodynamics is needed to fully model the intracluster medium (ICM); however, as we move to more sophisticated models, it is important to consider the role of magnetic fields and the way the fluid…

Magnetic buoyancy (MBI) and Parker instabilities are strong, generic instabilities expected to occur in most astrophysical systems with sufficiently strong magnetic fields. In galactic and accretion discs, large-scale magnetic fields are…

By following the Kazantsev theory and taking into account both microscopic and turbulent diffusion of magnetic fields, we develop a unified treatment of the kinematic and nonlinear stages of turbulent dynamo, and study the dynamo process…

We report an extensive numerical study of the small-scale turbulent dynamo at large magnetic Prandtl numbers Pm. A Pm scan is given for the model case of low-Reynolds-number turbulence. We concentrate on three topics: magnetic-energy…

We construct parameter sets of the relativistic mean-field model fitted to the recent constraints on the asymmetry energy $J$ and the slope parameter $L$ for pure neutron matter. We find cases of unphysical behaviour, i.e.\ the appearance…

Magnetic fields pervade astrophysical systems and strongly influence their dynamics. Because magnetic diffusion is usually much faster than system evolution, ancient fields cannot explain the present magnetization of planets, stars, and…

We investigate the stellar kinematics of a sample of galaxies extracted from the hydrodynamic cosmological Magneticum Pathfinder simulations out to $5$ half-mass radii. We construct differential radial stellar spin profiles quantified by…

Radio observations show that magnetic fields are present in dwarf irregular galaxies (dIrr) and its strength is comparable to that found in spiral galaxies. Slow rotation, weak shear and shallow gravitational potential are the main features…

In dilute astrophysical plasmas, the collisional mean free path of a particle can exceed its Larmor radius. Under these conditions, the thermal conductivity and viscosity of the plasma can be dramatically altered. This alteration allows…

Spiral galaxies host dynamically important magnetic fields which can affect gas flows in the disks and halos. Total magnetic fields in spiral galaxies are strongest (up to 30 \muG) in the spiral arms where they are mostly turbulent or…

Mean field dynamos may explain the origin of large scale magnetic fields of galaxies, but controversy arises over the extent of dynamo quenching by the growing field. Here we explain how apparently conflicting results may be mutually…

The possibility of generating a magnetic field by dynamo effect with anisotropic electrical conductivity rather than turbulent flow has been demonstrated theoretically (Plunian & Alboussi\`ere 2020) and experimentally (Alboussi\`ere et al.…

The onset and evolution of magnetic fields in laboratory and astrophysical plasmas is determined by several mechanisms, including instabilities, dynamo effects and ultra-high energy particle flows through gas, plasma and interstellar-media.…

Neutron stars, and magnetars in particular, are known to host the strongest magnetic fields in the Universe. The origin of these strong fields is a matter of controversy. In this preliminary work, via numerical simulations, we study, for…