English
Related papers

Related papers: Electromagnetic helicity flux density for radiativ…

200 papers

Relativistic dynamics of distributed mass and charge densities of the extended classical particle is discussed for arbitrary gravitational and electromagnetic fields. Vector geodesic relations for material space densities are consequences…

General Physics · Physics 2012-12-04 I. E. Bulyzhenkov

We derive an expression for the macroscopic force density that a narrow-band electromagnetic field imposes on a dissipative isotropic medium. The result is obtained by averaging the microscopic form for Lorentz force density. The derived…

Optics · Physics 2015-05-20 Andriy Shevchenko , Matti Kaivola

We construct a magnetic helicity conserving dynamo theory which incorporates a calculated magnetic helicity current. In this model the fluid helicity plays a small role in large scale magnetic field generation. Instead, the dynamo process…

Astrophysics · Physics 2009-10-31 Ethan T. Vishniac , Jungyeon Cho

We investigate analytically the amplification of a weak magnetic field in a homogeneous and isotropic turbulent flow lacking reflectional symmetry (helical turbulence). We propose that the spectral distributions of magnetic energy and…

Astrophysics · Physics 2007-05-23 Stanislav Boldyrev , Fausto Cattaneo , Robert Rosner

We examine the force of the electromagnetic radiation on linear, isotropic, homogeneous media specified in terms of their permittivity epsilon and permeability mu. A formula is proposed for the electromagnetic Lorentz force on the…

Optics · Physics 2014-01-31 Masud Mansuripur

Here we discuss the free energy of nematic liquid crystals using two vectors and the helicity, with the aim of having a compact form of its density. The two vectors are due to the splay and bend distortions of the director field. They have…

Soft Condensed Matter · Physics 2018-05-01 Amelia Carolina Sparavigna

We calculate the electromagnetic (EM) form factors of the pseudoscalar mesons in the light-front framework. Specifically, these form factors are extracted from the relevant matrix elements directly, instead of choosing the Breit frame. The…

High Energy Physics - Phenomenology · Physics 2011-09-13 Chien-Wen Hwang

In turbulent dynamos the production of large-scale magnetic fields is accompanied by a separation of magnetic helicity in scale. The large- and small-scale parts increase in magnitude. The small-scale part can eventually work against the…

Solar and Stellar Astrophysics · Physics 2011-08-24 Simon Candelaresi , Axel Brandenburg

We discuss here the effect of the photon helicity in laser induced and inverse bremstrahlung for {\it high energy scattering} of electrons by hydrogen atoms. We demonstrate that it is possible to find EDAD for high scattering energies of…

Atomic Physics · Physics 2013-02-08 Aurelia Cionga , Fritz Ehlotzky , Gabriela Zloh

We recently proposed a method to calculate the relative magnetic helicity in a finite volume for a given magnetic field which however required the flux to be balanced separately on all the sides of the considered volume. In order to allow…

Solar and Stellar Astrophysics · Physics 2018-05-30 Shangbin Yang , Joerg Buechner , Jan Skala , Hongqi Zhang

We study the effect of turbulent drift of a large-scale magnetic field that results from the interaction of helical convective motions and differential rotation in the solar convection zone. The principal direction of the drift corresponds…

Solar and Stellar Astrophysics · Physics 2015-06-05 V. V. Pipin

The constraint imposed by magnetic helicity conservation on the alpha effect is considered for both magnetically and flow dominated self-organizing plasmas. Direct numerical simulations are presented for a dominant contribution to the alpha…

High Energy Astrophysical Phenomena · Physics 2015-06-18 F. Ebrahimi , A. Bhattacharjee

Swimming microorganisms often have to propel in complex, non-Newtonian fluids. We carry out experiments with self-propelling helical swimmers driven by an externally rotating magnetic field in shear-thinning, inelastic fluids. Similarly to…

Fluid Dynamics · Physics 2017-03-08 Saul Gomez , Francisco Godinez , Eric Lauga , Roberto Zenit

We determine the invariant expression of the force density that the electromagnetic field exerts on dipolar matter and construct the non-symmetric energy-momentum tensor of the electromagnetic field in matter which is consistent with that…

Classical Physics · Physics 2017-11-17 Rodrigo Medina , J. Stephany

We put forward the physical meaning of the conservation equation for the helicity on scattering of an electromagnetic field with a generally magnetodielectric bi-isotropic dipolar object. This is the optical theorem for the helicity that,…

Optics · Physics 2015-11-05 Manuel Nieto-Vesperinas

Helicity measures complexity in the field. Magnetic helicity is given by a volume integral over the scalar product of magnetic field {\bf B} and its vector potential {\bf A}. A direct computation of magnetic helicity in the solar atmosphere…

Solar and Stellar Astrophysics · Physics 2015-05-20 Sanjiv Kumar Tiwari

We study the behaviour of shocked wind-electrons leaving wind-driving stars after undergoing the outer wind termination shock. As an example, we describe the evolution of the keV-energetic electron distribution function downstream of the…

Space Physics · Physics 2019-01-23 Hans J. Fahr , Robindro Dutta-Roy

We study electromagnetic streaming instabilities in thermal viscous regions of rotating astrophysical objects, such as, magnetized accretion disks, molecular clouds, their cores, and elephant trunks. The obtained results can also be applied…

Astrophysics of Galaxies · Physics 2015-05-14 Anatoly Nekrasov

We study the thermal helicity, defined in arXiv:1211.3850, of a conformal field theory with anomalies in the context of AdS$_{2n+1}$/CFT$_{2n}$. To do so, we consider large charged rotating AdS black holes in the…

High Energy Physics - Theory · Physics 2015-06-17 Tatsuo Azeyanagi , R. Loganayagam , Gim Seng Ng , Maria J. Rodriguez

In this paper we study the effects of hemispheric imbalance of magnetic helicity density on breaking the equatorial reflection symmetry of the dynamo generated large-scale magnetic field. Our study employs the axisymmetric dynamo model…

Solar and Stellar Astrophysics · Physics 2020-06-17 S. Yang , V. V. Pipin , D. D. Sokoloff , K. M. Kuzanyan , H. Zhang