HR: 0800h
AN: SH11B-0266    [Abstracts]
TI: Identifying the solar sources of helium variation in the slow solar wind using global MHD simulations
AU: * Stevens, M L
EM: mike@space.mit.edu
AF: MIT Kavli Institute for Astrophysics and Space Research, 77 Massachusetts Ave, Cambridge, MA 02139 United States
AU: Kasper, J C
EM: jck@space.mit.edu
AF: MIT Kavli Institute for Astrophysics and Space Research, 77 Massachusetts Ave, Cambridge, MA 02139 United States
AU: Lazarus, A J
EM: ajl@space.mit.edu
AF: MIT Kavli Institute for Astrophysics and Space Research, 77 Massachusetts Ave, Cambridge, MA 02139 United States
AU: Steinberg, J T
EM: jsteinberg@lanl.gov
AF: Los Alamos National Laboratory, Mail Stop D466, Los Alamos, NM 87545 United States
AU: Riley, P
EM: pete.riley@saic.com
AF: Science Applications International Corporation, 10260 Campus Point Drive, San Diego, CA 92121 United States
AB: As the second most abundant element in the heliosphere, helium plays a significant role in the dynamics of the solar interior, corona, and solar wind. The relative abundance by number density of helium to hydrogen (He/H) in the solar wind plasma can vary by factors of hundreds, with typical values in the undisturbed solar wind rarely exceeding 5%. During solar minimum, He/H is a linear function of speed, while at solar maximum He/H is 4.5% on average at all speeds. There are periods at solar maximum where the distribution of He/H is bi-modal, with one peak at the solar maximum 4.5%, and a second, smaller peak at the speed-dependent solar minimum value. We have combined interplanetary measurements of He/H from the Wind spacecraft with derived plasma flow from the MAS 3D MHD coronal model of the solar corona and inner heliosphere to identify the source regions of the slow solar wind that produce these distinct helium populations.
DE: 2162 Solar cycle variations (7536)
DE: 2164 Solar wind plasma
DE: 2169 Solar wind sources
SC: SPA-Solar and Heliospheric Physics [SH]
MN: Fall Meeting 2005