HR: 14:25h
AN: SH13B-04    [Abstracts]
TI: Preferential Perpendicular Heating of Coronal Hole Heavy Ions by the Fermi Mechanism
AU: * Isenberg, P A
EM: phil.isenberg@unh.edu
AF: Institute for the Study of Earth,Oceans and Space, University of New Hampshire, Morse Hall 39 College Road, Durham, NH 03824 United States
AU: Vasquez, B J
EM: bernie.vasquez@unh.edu
AF: Institute for the Study of Earth,Oceans and Space, University of New Hampshire, Morse Hall 39 College Road, Durham, NH 03824 United States
AB: One of the most peculiar features of the fast solar wind is the preferential energization of heavy ions (those more massive than protons). Observations by UVCS/SOHO have shown that much of this preferential heating takes place within 4 solar radii in coronal holes. The observed preferential acceleration naturally follows from the perpendicular heating in a radially decreasing magnetic field. We demonstrate that this perpendicular heating can result from the cyclotron resonant interaction with both inward and outward propagating ion cyclotron waves, yielding a low-energy form of Fermi acceleration. This process is not available to protons, so a preferential heating results. We will present the equations describing this process and discuss results from a computational model.
DE: 7511 Coronal holes
DE: 7827 Kinetic and MHD theory
DE: 7836 MHD waves and instabilities (2149, 2752, 6050)
DE: 7846 Plasma energization
DE: 7867 Wave/particle interactions (2483, 6984)
SC: SPA-Solar and Heliospheric Physics [SH]
MN: Fall Meeting 2005