Astronomy and Astrophysics – Astronomy
Scientific paper
Dec 2010
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2010apj...725.2128w&link_type=abstract
The Astrophysical Journal, Volume 725, Issue 2, pp. 2128-2151 (2010).
Astronomy and Astrophysics
Astronomy
3
Magnetohydrodynamics: Mhd, Solar Wind, Sun: Magnetic Topology, Waves
Scientific paper
The magnetic helicity characteristics of fully nonlinear, multi-dimensional Alfvén simple waves are investigated, by using relative helicity formulae and also by using an approach involving poloidal and toroidal decomposition of the magnetic field and magnetic vector potential. Different methods to calculate the magnetic vector potential are used, including the homotopy and Biot-Savart formulae. Two basic Alfvén modes are identified: (1) the plane one-dimensional Alfvén simple wave given in standard texts, in which the Alfvén wave propagates along the z-axis with wave phase phiv = k 0(z - λt), where k 0 is the wave number and λ is the group velocity of the wave and (2) the generalized Barnes simple Alfvén wave in which the wave normal n moves in a circle in the xy-plane perpendicular to the mean field, which is directed along the z-axis. The plane Alfvén wave (1) is analogous to the slab Alfvén mode and the generalized Barnes solution (2) is analogous to the two-dimensional mode in Alfvénic, incompressible turbulence. The helicity characteristics of these two basic Alfvén modes are distinct. The helicity characteristics of more general multi-dimensional simple Alfvén waves are also investigated. Applications to nonlinear Alfvénic fluctuations and structures observed in the solar wind are discussed.
Dasgupta Basudeb
Hu Qiang
Roberts Daniel A.
Webb Gary M.
Zank Gary P.
No associations
LandOfFree
Alfvén Simple Waves: Euler Potentials and Magnetic Helicity does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Alfvén Simple Waves: Euler Potentials and Magnetic Helicity, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Alfvén Simple Waves: Euler Potentials and Magnetic Helicity will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1478851