Hostname: page-component-74656f9884-8r8nv Total loading time: 0 Render date: 2026-11-10T12:03:01.298Z Has data issue: false hasContentIssue false

Double Alfvén waves

Published online by Cambridge University Press:  17 October 2011

G. M. WEBB
Affiliation:
CSPAR, The University of Alabama in Huntsville, Huntsville AL 35805, USA (gmw0002@uah.edu)
Q. HU
Affiliation:
CSPAR, The University of Alabama in Huntsville, Huntsville AL 35805, USA (gmw0002@uah.edu)
B. DASGUPTA
Affiliation:
CSPAR, The University of Alabama in Huntsville, Huntsville AL 35805, USA (gmw0002@uah.edu)
G. P. ZANK
Affiliation:
CSPAR, The University of Alabama in Huntsville, Huntsville AL 35805, USA (gmw0002@uah.edu) Department of Physics, The University of Alabama in Huntsville, Huntsville AL 35899, USA
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the 'Save PDF' action button.

Double Alfvén wave solutions of the magnetohydrodynamic equations in which the physical variables (the gas density ρ, fluid velocity u, gas pressure p, and magnetic field induction B) depend only on two independent wave phases ϕ1(x,t) and ϕ2(x,t) are obtained. The integrals for the double Alfvén wave are the same as for simple waves, namely, the gas pressure, magnetic pressure, and group velocity of the wave are constant. Compatibility conditions on the evolution of the magnetic field B due to changes in ϕ1 and ϕ2, as well as constraints due to Gauss's law ∇ · B = 0 are discussed. The magnetic field lines and hodographs of B in which the tip of the magnetic field B moves on the sphere |B| = B = const. are used to delineate the physical characteristics of the wave. Hamilton's equations for the simple Alfvén wave with wave normal n(ϕ), and with magnetic induction B(ϕ) in which ϕ is the wave phase, are obtained by using the Frenet–Serret equations for curves x=X(ϕ) in differential geometry. The use of differential geometry of 2D surfaces in a 3D Euclidean space to describe double Alfvén waves is briefly discussed.

Information

Type
Papers
Copyright
Copyright © Cambridge University Press 2011