HR: 1340h
AN: SH23B-0341    [Abstracts]
TI: The Effect of a Fisk-Parker Hybrid Magnetic Field on 26-day Recurrent Cosmic-Ray Variations
AU: Kruger, T P
EM: fsktpjk@puk.ac.za
AF: North-West University, Unit for Space Physics North-West University, Potchefstroom, 2520
AU: * Burger, R A
EM: fskrab@puk.ac.za
AF: North-West University, Unit for Space Physics North-West University, Potchefstroom, 2520
AU: Hitge, M
EM: wskmh@puk.ac.za
AF: North-West University, Unit for Space Physics North-West University, Potchefstroom, 2520
AB: The occurrence of 26-day recurrent cosmic-ray intensity variations follows naturally from Fisk-type heliospheric magnetic fields. This was demonstrated by Burger and Hitge (2004, ApJL, 617) who used a divergence-free Fisk-Parker hybrid field. This approach has been refined (Kruger, 2005, M.Sc. thesis, North-West University, in preparation) and we present the latest results. The steady-state three-dimensional version of Parker's transport equation for cosmic rays is solved numerically for both protons and for electrons. Following Burger and Hitge (2004), we model the amplitude of 26-day recurrent variations of both protons and electrons as function of the latitudinal gradient, but now also as function of heliolatitude. We will also use the phase difference between the variations of the two species, and study the role of the wavy current sheet, to determine whether a Fisk-type field can account for the observed properties of 26-day cosmic-ray variations at all latitudes covered by the Ulysses mission.
DE: 2104 Cosmic rays
DE: 2126 Heliosphere/interstellar medium interactions
DE: 2134 Interplanetary magnetic fields
SC: SPA-Solar and Heliospheric Physics [SH]
MN: Fall Meeting 2005