Abstract
Within the MHD approximation, the Alfvén mode is the only hydromagnetic wave mode in which the field‐aligned current can be nonzero. By means of the two‐fluid equations, it is shown that the finite‐Larmor‐radius effect is responsible for the field‐aligned currents in the fast and slow modes and for the compressibility in the Alfvén mode. These results are useful in understanding the time‐dependent field‐aligned current sheets associated with auroral arcs with thickness down to the ion gyroradius scale.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
