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Related papers: A Conserved Cross Helicity for Non-Barotropic MHD

200 papers

Symmetry plays a fundamentally important role in physics. In this work, we find a conservation law, $S^{\dagger}(H_{c}^{\dagger})S(H_{c})=I$, which is valid for any non-Hermitian scattering center $H_c$. As a result, the reflections and…

Quantum Physics · Physics 2023-10-05 H. S. Xu , L. Jin

Relative magnetic helicity is conserved by magneto-hydrodynamic evolution even in the presence of moderate resistivity. For that reason, it is often invoked as the most relevant constraint to the dynamical evolution of plasmas in complex…

Solar and Stellar Astrophysics · Physics 2020-10-28 Gherardo Valori , Pascal Démoulin , Etienne Pariat , Anthony Yeates , Kostas Moraitis , Luis Linan

In this work we extend our previously developed formalism of Newtonian multi-fluid hydrodynamics to allow for coupling between the fluids and the electromagnetic and gravitational field. This is achieved within the convective variational…

Fluid Dynamics · Physics 2009-11-11 Reinhard Prix

In the presence of large-scale vortical motions and/or magnetic-field strains, the turbulent cross helicity (velocity--magnetic-field correlation in fluctuations) may contribute to the turbulent electromotive force and the Reynolds stress.…

Solar and Stellar Astrophysics · Physics 2015-05-28 Nobumitsu Yokoi , Guillaume Balarac

The study investigates the problem of magnetohydrodynamic (MHD) free convection over a non-isothermal axisymmetric body under the action of transverse magnetic field. The body is embedded in a porous medium saturated with electrically…

Mathematical Physics · Physics 2013-10-01 Shobha Bagai , Chandrashekhar Nishad

We discuss optical chirality in different types of gyrotropic media. Our analysis is based on the formalism of nongeometric symmetries of Maxwell's equations in vacuum generalized to material media with given constituent relations. This…

Other Condensed Matter · Physics 2017-06-22 Igor Proskurin , Alexander S. Ovchinnikov , Pavel Nosov , Jun-ichiro Kishine

We present numerical simulations and explore scalings and anisotropy of compressible magnetohydrodynamic (MHD) turbulence. Our study covers both gas pressure dominated (high beta) and magnetically dominated (low beta) plasmas at different…

Astrophysics · Physics 2011-05-05 Jungyeon Cho , A. Lazarian

In this paper, we are concerned with the Kolmogorov's scaling laws of conserved quantities. By means of Eyink's longitudinal structure functions and the analysis of interaction of different physical quantities, we extend celebrated…

Analysis of PDEs · Mathematics 2024-04-11 Yulin Ye , Yanqing Wang , Otto Chkhetiani

Magnetic fields play an important role in many astrophysical systems and a detailed understanding of their impact on the gas dynamics requires robust numerical simulations. Here we present a new method to evolve the ideal…

Instrumentation and Methods for Astrophysics · Physics 2015-06-18 Philip Mocz , Mark Vogelsberger , Lars Hernquist

Galactic HI is a gas that is coupled to magnetic field because of its fractional ionization. Many properties of HI are affected by turbulence. Recently, there has been a significant breakthrough on the theory of magnetohydrodynamic (MHD)…

Astrophysics · Physics 2007-05-23 Jungyeon Cho , Alex Lazarian , Huirong Yan

The effect of non-commutativity on electromagnetic waves violates Lorentz invariance: in the presence of a background magnetic induction field b, the velocity for propagation transverse to b differs from c, while propagation along b is…

High Energy Physics - Theory · Physics 2009-11-07 Z. Guralnik , R. Jackiw , S. Y. Pi , A. P. Polychronakos

Over the past two decades, open systems that are described by a non-Hermitian Hamiltonian have become a subject of intense research. These systems encompass classical wave systems with balanced gain and loss, semiclassical models with mode…

Quantum Physics · Physics 2021-10-27 Frantisek Ruzicka , Kaustubh S. Agarwal , Yogesh N. Joglekar

Hybrid kinetic-MHD models describe the interaction of an MHD bulk fluid with an ensemble of hot particles, which is described by a kinetic equation. When the Vlasov description is adopted for the energetic particles, different Vlasov-MHD…

Plasma Physics · Physics 2017-03-21 Joshua W. Burby , Cesare Tronci

A new regularisation of the shallow water (and isentropic Euler) equations is proposed. The regularised equations are non-dissipative, non-dispersive and possess a variational structure. Thus, the mass, the momentum and the energy are…

Fluid Dynamics · Physics 2020-02-20 Didier Clamond , Denys Dutykh

We derive error estimates of a finite element method for the approximation of solutions to a seven-fields formulation of a magnetohydrodynamics model, which preserves the energy of the system, and the magnetic and cross helicities on the…

Numerical Analysis · Mathematics 2025-03-04 L. Beirao da Veiga , K. Hu , L. Mascotto

A new class of analytical 2-D solutions of the full set of the steady magnetohydrodynamic (MHD) equations, describing an axisymmetric helicoidal magnetized outflow originating from a rotating central object, is presented. The solutions are…

Astrophysics · Physics 2009-11-06 J. J. G. Lima , E. R. Priest , K. Tsinganos

A four-field reduced model of single helicity, incompressible MHD is derived in cylindrical geometry. An appropriate set of noncanonical variables is found, and the Hamiltonian, the Lie-Poisson bracket and the Casimir invariants are…

Plasma Physics · Physics 2024-12-03 M. Furukawa , M. Hirota

Magnetic helicity is a fundamental quantity of magnetohydrodynamics that carries topological information about the magnetic field. By `topological information', we usually refer to the linkage of magnetic field lines. For domains that are…

Plasma Physics · Physics 2019-09-25 David MacTaggart , Alberto Valli

This paper investigates hybrid kinetic-MHD models, where a hot plasma (governed by a kinetic theory) interacts with a fluid bulk (governed by MHD). Different nonlinear coupling schemes are reviewed, including the pressure-coupling scheme…

Plasma Physics · Physics 2014-07-10 Cesare Tronci , Emanuele Tassi , Enrico Camporeale , Philip J. Morrison

Helicity preserving nanostructures and metasurfaces have been recently proposed as suitable candidates to enhance spectroscopic features of chiral matter. With this in mind, we highlight that losses in the constituent nonmagnetic materials…