HR: 1340h
AN: SH53A-1254    [Abstracts]
TI: Alfvénic Turbulence and Micro-Stream Structure in the Polar Solar Wind.
AU: Landi, S
EM: slandi@arcetri.astro.it
AF: Dipartimento di Astronomia, Universit… di Firenze, Largo E Fermi 2, Firenze, FI 50125 Italy
AU: * Velli, M
EM: velli@arcetri.astro.it
AF: Dipartimento di Astronomia, Universit… di Firenze, Largo E Fermi 2, Firenze, FI 50125 Italy
AU: * Velli, M
EM: velli@arcetri.astro.it
AF: Jet Propulsion Laboratory, 4800 Oak Grove Dr., Pasadena, CA 91109 United States
AU: Hellinger, P
EM: petr.hellinger@ufa.cas.cz
AF: Institute of Atmospheric Physics, ASCR, Prague, 14131 Czech Republic
AU: Neugebauer, M
EM: mneugeb@lpl.arizona.edu
AF: Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721 United States
AB: We present 2D simulations of the interaction of an outwardly propagating Alfvén wave spectrum with micro-streams in the expanding solar wind. In previous work, we suggested that velocity shears in the developing solar wind could be responsible for the high-latitude polarity reversals observed by Ulysses. Here we carry out numerical experiments with more realistic initial conditions. We suggest that Alfvénic turbulence might play a role in determining the overall velocity differences in a stream- or jet- dominated early fast wind, surviving further out as the microstream structures, since turbulence may act as a sink for free energy in velocity shears. The magnitude of velocity shears at large distances from the sun is determined by the interplay of turbulent dissipation and magnetic tension. We compare simulation results with representative data from the Ulysses measurements.
DE: 7524 Magnetic fields
DE: 7839 Nonlinear phenomena (4400, 6944)
DE: 7863 Turbulence (4490)
SC: SPA-Solar and Heliospheric Physics [SH]
MN: Fall Meeting 2005