HR: 15:45h
AN: SH24A-02 INVITED     [Abstracts]
TI: Applications of the Potential Field Source Surface Model in CME and solar wind studies*
AU: * Li, Y
EM: yanli@ssl.berkeley.edu
AF: SSL University of California Berkeley, 7 Gauss Way, Berkeley, CA 94720 United States
AU: Luhmann, J G
AF: SSL University of California Berkeley, 7 Gauss Way, Berkeley, CA 94720 United States
AB: With various collaborators we have used the PFSS model to: 1) investigate topological changes in the coronal magnetic field related to active region strength, location and orientation within the background photospheric field; 2) investigate the relationship between large scale coronal magnetic field changes and the occurrence of CMEs; and 3) investigate the solar cycle variation of solar wind sources. Our experiences with the model, which is extremely versatile and easy to implement relative to magnetogram-based global force-free or MHD models, have been surprisingly positive considering the known physical shortcomings of the underlying assumptions. As long as one always keeps in mind the expected limitations of the potential field and spherical source surface assumptions, PFSS model makes it possible to approximate coronal open field regions as accurately as MHD models (or more so at the current state of MHD global modeling, depending on the latter's spatial resolution and resistivity properties), to describe coronal features observed in some CME event case studies, and to visualize the characteristics of a spherical geometry on null points and topological field domains related to a particular photospheric field distribution. Global potential model has often been used to be the initial state of a MHD model simulation. When viewed as a tool in the arsenal of solar physics, rather than as an end model, the PFSS approach opens the door to many applications that set the stage for later more sophisticated modeling. *work suppoted by DOD/solarMURI, the Center for Integrated Space Weather Modeling (an NSF Science and Technology Center), and NSF/ATM.
DE: 2169 Sources of the solar wind
DE: 7500 SOLAR PHYSICS, ASTROPHYSICS, AND ASTRONOMY
DE: 7511 Coronal holes
DE: 7513 Coronal mass ejections
DE: 7524 Magnetic fields
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2005 Joint Assembly