Premium
Alfvénic tornadoes in a magnetized plasma
Author(s) -
Shukla P. K.
Publication year - 2013
Publication title -
journal of geophysical research: space physics
Language(s) - English
Resource type - Journals
eISSN - 2169-9402
pISSN - 2169-9380
DOI - 10.1029/2012ja018247
Subject(s) - physics , plasma , magnetic field , angular momentum , vortex , atomic physics , kinetic energy , alfvén wave , electron , magnetohydrodynamics , solar wind , computational physics , classical mechanics , mechanics , quantum mechanics
It is shown that three‐dimensional (3D) modified‐kinetic Alfvén waves (m‐KAWs) in a magnetized plasma can propagate in the form of Alfvénic tornadoes characterized by plasma density whirls or magnetic flux ropes carrying orbital angular momentum. By using the two‐fluid model, together with Ampère's law, we derive the wave equation for 3D m‐KAWs in a magnetoplasma with m e / m i ≪ β ≪ 1, where m e ( m i ) is the electron (ion) mass, β = 4 π n 0 k BT e + T i/ B 0 2 , n 0 the unperturbed plasma number density, k B the Boltzmann constant, T e ( T e ) the electron (ion) temperature, and B 0 the strength of the ambient magnetic field. The 3D m‐KAW equation admits solutions in the form of a Laguerre‐Gauss Alfvénic vortex beam or a twisted kinetic Alfvénic wave with plasma density whirls that support the dynamics of shear Alfvénic magnetic flux ropes in plasmas.