HR: 1330h
AN: SH13A-04    [Abstracts]
TI: Determining the Sources of Solar Wind using Potential Field Models and In Situ Measurements
AU: Neugebauer, M C
EM: mneugeb@lpl.arizona.edu
AF: Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721 United States
AU: * Liewer, P C
EM: paulett.liewer@jpl.nasa.gov
AF: Jet Propulsion Laboratory, Mail Stop 169-506, Pasadena, CA 91109 United States
AB: This paper summarizes our studies of solar wind sources, both near solar maximum and solar minimum, using potential field models and ACE, Wind, and Ulysses measurements. In these studies, both MHD mapping and two-step (ballistic plus potential magnetic field) reverse mapping of solar wind from ACE, Wind, and Ulysses to the solar surface were used to determine the solar source regions of the sampled wind. At solar minimum, the wind mapped to both polar and near-equatorial coronal holes. At solar maximum, both coronal holes (as seen in Helium 10830 A) and active regions were sources of solar wind. A source was attributed to an active region if the mapped footpoints matched open flux in a region of strong magnetic field with no nearby coronal hole visible in the NSO He 10830 � synoptic coronal hole maps. We found that the solar wind from these active regions had distinct signatures, e.g., it generally had a higher oxygen charge state than wind associated with Helium-10830� coronal hole sources, indicating a hotter source region. We also found correlations of the magnetic topology of the open field lines of these active region sources with images of the hot corona in EUV and soft X-ray images. The active-region flows appeared to be organized into several substreams, unlike the more monolithic structure of flows from coronal holes. The boundaries between plasma flows from neighboring sources were marked by large magnetic holes, plasma sheets, and low entropy, independent of whether the sources had the same or opposite magnetic polarities.
DE: 7509 Corona
DE: 7524 Magnetic fields
DE: 7536 Solar activity cycle (2162)
DE: 7811 Discontinuities
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2005 Joint Assembly