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Related papers: Magnetic helicity in multiply connected domains

200 papers

Roles of turbulence in the context of magnetic reconnection are investigated with special emphasis on the mutual interaction between flow (large-scale inhomogeneous structure) and turbulence. In order to evaluate the effective transport due…

Solar and Stellar Astrophysics · Physics 2015-05-28 Nobumitsu Yokoi , Masahiro Hoshino

We use the Hopf mapping to construct a magnetic configuration consisting of closed field lines, each of which is linked with all the other ones. We obtain in this way a solution of the equations of magnetohydrodynamics of an ideal…

Plasma Physics · Physics 2007-05-23 A. M. Kamchatnov

Magneto-inertial range dominated by magnetic helicity has been studied using results of numerical simulations, laboratory measurements, solar, solar wind, the Earth's and planets' magnetosphere observations (spacecraft measurements), and…

Space Physics · Physics 2024-05-22 A. Bershadskii

We study the writhe, twist and magnetic helicity of different magnetic flux ropes, based on models of the solar coronal magnetic field structure. These include an analytical force-free Titov--D\'emoulin equilibrium solution, non force-free…

Solar and Stellar Astrophysics · Physics 2017-05-10 Y. Guo , E. Pariat , G. Valori , S. Anfinogentov , F. Chen , M. Georgoulis , Y. Liu , K. Moraitis , J. K. Thalmann , S. Yang

Much work on turbulent three-dimensional dynamos has been done using triply periodic domains, in which there are no magnetic helicity fluxes. Here we present simulations where the turbulent intensity is still nearly homogeneous, but now…

Solar and Stellar Astrophysics · Physics 2019-02-20 A. Brandenburg

Electromagnetic quantities such as energy density, momentum, spin, and helicity bring meaning and intuition to electromagnetism and possess intricate interrelations, particularly prominent in complex non-paraxial near-fields. These…

Magnetohydrodynamics (MHD) provides the simplest description of magnetic plasma turbulence in a variety of astrophysical and laboratory systems. MHD turbulence with nonzero cross helicity is often called imbalanced, as it implies that the…

Astrophysics of Galaxies · Physics 2015-05-18 Jean Carlos Perez , Stanislav Boldyrev

The hypermagnetic helicity density at the electroweak phase transition (EWPT) exceeds many orders of magnitude the galactic magnetic helicity density. Together with previous magnetic helicity evolution calculations after the EWPT and…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 V. B. Semikoz , D. Sokoloff , J. W. F. Valle

We study the inverse cascade of magnetic helicity in conducting fluids by investigating the detailed transfer of helicity between different spherical shells in Fourier space in direct numerical simulations of three-dimensional…

Plasma Physics · Physics 2009-11-11 Alexandros Alexakis , Pablo Mininni , Annick Pouquet

A topological flux function is introduced to quantify the topology of magnetic braids: non-zero line-tied magnetic fields whose field lines all connect between two boundaries. This scalar function is an ideal invariant defined on a…

Plasma Physics · Physics 2015-06-15 A. R. Yeates , G. Hornig

We discuss inverse problem of detection turbulence magnetic field helical properties using radio survey observations statistics. In this paper, we present principal solution which connects magnetic helicity and correlation between Faraday…

Instrumentation and Methods for Astrophysics · Physics 2010-01-19 A. Volegova , R. Stepanov

Helicity is a fundamental conserved quantity in physical systems governed by vector fields whose evolution is described by volume-preserving transformations on a three-manifold. Notable examples include inviscid, incompressible fluid flows,…

Symplectic Geometry · Mathematics 2025-08-15 Oliver Edtmair , Sobhan Seyfaddini

Magnetic fields in various astrophysical settings may be helical and, in the cosmological context, may provide a measure of primordial CP violation during baryogenesis. Yet it is difficult, even in principle, to devise a scheme by which…

Astrophysics · Physics 2009-11-13 Tina Kahniashvili , Tanmay Vachaspati

We prove that any regular Casimir in 3D magnetohydrodynamics is a function of the magnetic helicity and cross-helicity. In other words, these two helicities are the only independent regular integral invariants of the coadjoint action of the…

Mathematical Physics · Physics 2019-01-15 Boris Khesin , Daniel Peralta-Salas , Cheng Yang

The topology and dynamics of the three-dimensional magnetic field in the solar atmosphere govern various solar eruptive phenomena and activities, such as flares, coronal mass ejections, and filaments/prominences. We have to observe and…

Solar and Stellar Astrophysics · Physics 2017-06-20 Yang Guo , Xin Cheng , M. D. Ding

We show that the helicity flux density is distinguished from magnetic helicity by analysing Hopf solitons. The electromagnetic (EM) helicity flux and the magnetic helicity are Chern-Simons terms at different hypersurfaces. We find the…

High Energy Physics - Theory · Physics 2026-01-01 Zhen-Yu Heng , Jiang Long , Run-Ze Yu , Xin-Hao Zhou

It is shown that the helicity amplitudes can be used to describe and analyze the properties of the electromagnetic field in classical and in quantum theory. On the one hand they embody the relativistic content of electromagnetic theory. On…

Optics · Physics 2019-08-06 Iwo Bialynicki-Birula

We perform direct numerical simulations of magnetohydrodynamic (MHD) turbulence with kinetic energy and cross helicity injections at large scales. We observe that the cross helicity changes sign as we go from large and intermediate scales…

Plasma Physics · Physics 2020-01-10 V. Titov , R. Stepanov , N. Yokoi , M. Verma , R. Samtaney

It is demonstrated that the two-point correlation function of the magnetic helicity in the case of zero mean magnetic field has anomalous scalings for both, compressible and incompressible turbulent helical fluid flow. The magnetic helicity…

Astrophysics · Physics 2009-11-07 I. Rogachevskii , N. Kleeorin

We compute for the first time magnetic helicity and energy spectra of the solar active region NOAA 11158 during 11-15 February 2011 at 20^o southern heliographic latitude using observational photospheric vector magnetograms. We adopt the…

Solar and Stellar Astrophysics · Physics 2014-03-25 Hongqi Zhang , Axel Brandenburg , D. D. Sokoloff