The weakly non-linear interaction of slow magnetoacoustic and torsional Alfvén waves propagating along an unperturbed poloidal magnetic field in a stellar interior is studied in the high plasma β limit. It is shown that slow magnetoacoustic waves parametrically drive torsional modes with the half frequency and wave number. Therefore global slow magnetoacoustic waves which have a radial velocity...

Extending our previous results for artificial viscosity systems, we show, under suitable spectral hypotheses, that shock wave solutions of compressible Navier–Stokes (cNS) and magnetohydrodynamics (MHD) equations undergo Hopf bifurcation to nearby time-periodic solutions. The main new difficulty associated with physical viscosity and the corresponding absence of parabolic smoothing is the need ...

A simplified one-dimensional (1D) magnetohydrodynamics (MHD) is solved using a lattice Boltzmann and a quantum lattice gas model. It is shown that the magnetic field decreases the strength of the velocity shock fronts, with marked spikes in the magnetic field strength that gradually broaden in time. There is very good agreement between the lattice Boltzmann model—a representation of non-linear ...

This paper establishes the local-in-time existence and uniqueness of solutions to the viscous, non-resistive magnetohydrodynamics (MHD) equations in R , where d = 2, 3, with initial data B0 ∈ H (R) and u0 ∈ H s−1+ε(Rd) for s > d/2 and any 0 < ε < 1. The proof relies on maximal regularity estimates for the Stokes equation. The obstruction to taking ε = 0 is explained by the failure of solutions ...

Key words galaxies: magnetic fields – magnetohydrodynamics (MHD) – turbulence We summarize the current state of the long term discussion about the saturation mechanisms associated with rapid growth of small-scale magnetic field, that operate in large-scale galactic dynamos, and related problems with magnetic helicity conservation. Our general conclusion is that, taking into account magnetic hel...

The energy functional of ideal magnetohydrodynamics (MHD) is extended to the regime finite resistivity and transformed into an intuitive form, which separates pressure-gradient, current-density drive stabilising phenomena, analogously version derived by Greene Johnson ( Plasma Phys. , vol. 10, issue 8, 1968, pp. 729–745). resulting resistive not in form a solvable eigenvalue problem but intende...

Observations of proton density fluctuations the solar wind at 1 au have shown presence a decade-long transition region spectrum above sub-ion scales, characterized by flattening spectral slope. We use data collected BMSW instrument on-board Spektr-R satellite in order to delimit plasma parameters under which can be observed. Under similar conditions those observations, we carry out 3D compressi...

In broad astrophysical contexts of large-scale gravitational collapses and outflows and as a basis for various further astrophysical applications, we formulate and investigate a theoretical problem of self-similar magnetohydrodynamics (MHD) for a non-rotating polytropic gas of quasi-spherical symmetry permeated by a completely random magnetic field. Within this framework, we derive two coupled ...

Thermal ionization is a critical process at temperatures T &gt; 10 3 K, particularly during star formation. An increase in leads to decrease nonideal magnetohydrodynamics (MHD) resistivities, which has significant impact on protoplanetary disks and protostar We developed an extension of the fast computational method presented our recent paper include thermal ionization. The model can be used in...

The Cauchy problem for 3D incompressible Hall-magnetohydrodynamics (Hall-MHD) system with fractional Laplacians $$(-\Delta )^{\frac{1}{2}}$$ is studied. well-posedness of Hall-MHD equations remains an open diffusion . First, global small-energy solutions general initial data in $$H^s$$ , $$s>\frac{5}{2}$$ proved. Second, a special class large-energy constructed, which the globally well-posed. p...