HR: 0800h
AN: SH51C-0285    [Abstracts]
TI: Effect of Latitudinal Dependence of Boundary Conditions on Transport of Turbulence in the Heliosphere
AU: * Matthaeus, W
EM: whm@udel.edu
AF: Bartol Research Institute, University of Delaware, Newark, DE 19716 United States
AU: Breech, B
EM: breech@eecis.udel.edu
AF: Bartol Research Institute, University of Delaware, Newark, DE 19716 United States
AU: Minnie, J
EM: fskjm@puk.ac.za
AF: Unit for Space Physics, North-West University, Potchefstroom, 2520 South Africa
AU: Parhi, S
EM: parhi@bartol.udel.edu
AF: Bartol Research Institute, University of Delaware, Newark, DE 19716 United States
AU: Bieber, J W
EM: john@bartol.udel.edu
AF: Bartol Research Institute, University of Delaware, Newark, DE 19716 United States
AU: Burger, R A
EM: fskrab@puknet.puk.ac.za
AF: Unit for Space Physics, North-West University, Potchefstroom, 2520 South Africa
AU: Oughton, S
EM: seano@waikato.ac.nz
AF: Department of Mathematics, University of Waikato, Hamilton, 3105 New Zealand
AU: Smith, C W
EM: chuck@briaxa.sr.unh.edu
AF: Space Science Center, University of New Hampshire, Durham, NH 03824 United States
AU: Isenberg, P A
EM: pai@bluemoon.sr.unh.edu
AF: Space Science Center, University of New Hampshire, Durham, NH 03824 United States
AB: A four equation MHD turbulence model describes the radial evolution of fluctuation energy, correlation scale, temperature, and cross-helicity in a specified spherically expanding solar wind flow. This model is solved numerically along every radial direction in our simulation domain, spanning the region from 0.3 AU to 100 AU, varying inner boundary conditions and parameters to account for latitudinal structure. The model involves, as parameters, the plasma shear, wind speed, and strength of pick-up ion driving, Karman-Taylor constants, a constant that depends upon turbulence geometry, and another that specifies the ratio of kinetic to magnetic energy in the fluctuations. Magnetic variance, correlation length, cross helicity and plasma temperature are given latitudinal dependence along the inner boundary at 0.3 AU. The solar wind speed, proton number density, and temperature profiles are chosen to be consistent with observations over Ulysses' first full polar orbit [McComas et al., J. Geophys. Res., 105, 10419, 2000]. A simple model of pick-up ions is employed at present, which we plan to improve, following Isenberg et al [ApJ, 592, 564 2003]. The early indication shows that the simulation results thus obtained can be brought into good agreement with Voyager and Ulysses observations using parameters and boundary conditions that are consistent with observations. An interesting feature is that a relatively high magnetic variance is required at high latitude at inner boundary to make reasonable comparisons with observations. Heating is suppressed in the inner heliosphere and at high latitudes by the cross helicity effect, and the Alfvenicity of the turbulence almost completely vanishes by 10 AU.
DE: 7839 Nonlinear phenomena
DE: 7863 Turbulence
DE: 2104 Cosmic rays
DE: 2114 Energetic particles, heliospheric (7514)
DE: 2149 MHD waves and turbulence
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2004 AGU Fall Meeting