HR: 1330h
AN: SH42B-0535    [PDF]
TI: MHD Waves in Magnetic Flux Concentrations
AU: * Bogdan, T J
EM: tom@ucar.edu
AF: National Center for Atmospheric Research, P.O. Box 3000, Boulder, CO 80307-3000 United States
AU: Carlsson, M
EM: Mats.Carlsson@uio.no.edu
AF: University of Oslo, Institute for Theoretical Astrophysics, Blindern, N-0315 Norway
AU: Hansteen, V
EM: Viggo.Hansteen@uio.no.edu
AF: University of Oslo, Institute for Theoretical Astrophysics, Blindern, N-0315 Norway
AU: Zita, E J
EM: zita@evergreen.edu
AF: The Evergreen State College, Faculty of Science, Olympia, WA 98505 United States
AU: Stein, R F
AF: Michigan State University, Department of Physics & Astronomy, East Lansing, MI 48824 United States
AU: McIntosh, S W
AF: Goddard Space Flight Center, NASA, Greenbelt, MD 20771 United States
AB: Results from 2D MHD simulations of waves in a stratified isothermal atmosphere will be presented and analyzed. The waves are generated by a localized piston source situated on the lower, photospheric, boundary of the computational domain. A combination of fast and slow magneto-atmospheric waves propagates with little mutual interaction until they encounter the surface where the sound speed and the Alfven speed are comparable in magnitude. The waves couple strongly in this region and emerge with different amplitudes and phases. Owing to this mode mixing and the large variation in the Alfven speed in the magneto-atmosphere, the fluctuations observed at a given location are often a superposition of both fast and slow waves which have traversed different paths and have undergone different transformations during their journies.
DE: 7507 Chromosphere
DE: 7524 Magnetic fields
DE: 7529 Photosphere
DE: 7827 Kinetic and MHD theory
DE: 7843 Numerical simulation studies
SC: SPA - Solar and Heliospheric Physics [SH]
MN: 2003 Fall Meeting