Understanding the Solar Sources of In Situ ObservationsThe solar wind can, to a good approximation be described as a two component flow with fast, tenuous, quiescent flow emanating from coronal holes, and slow, dense and variable flow associated with the boundary between open and closed magnetic fields. In spite of its simplicity, this picture naturally produces a range of complex heliospheric phenomena, including the presence, location, and orientation of corotating interaction regions and their associated shocks. In this study, we apply a two-step mapping technique, incorporating a magnetohydrodynamic model of the solar corona, to bring in situ observations h m Ulysses, WIND, and ACE back to the solar surface in an effort to determine some intrinsic properties of the quasi-steady solar wind. In particular, we find that a "layer" of approx. 35,000 h n exists between the Coronal Hole Boundary (CHB) and the fast solar wind, where the wind is slow and variable. We also- derive a velocity gradient within large polar coronal boles (that were present during Ulysses rapid latitude scan) as a function of distance from the CHB. We find that nu = 713 km/s + 3.2 d, where d is the angular distance from the CHB boundary in degrees.
Document ID
20040050568
Acquisition Source
Headquarters
Document Type
Other
Authors
Riley, Pete (Science Applications International Corp. San Diego, CA, United States)
Mikic, Zoran (Science Applications International Corp. San Diego, CA, United States)
Linker, Jon (Science Applications International Corp. San Diego, CA, United States)
Zurbuchen, Thomas H. (Michigan Univ. Ann Arbor, MI, United States)