S. E. Gibson (NASA GSFC/ NRC); Fran Bagenal (Univ. of Colorado); Doug Biesecker (Univ. of Birmingham); J. T. Hoeksema (Stanford Univ.); Lika Guhathakurta (NASA GSFC/Catholic Univ.); B. J. Thompson (NASA GSFC/ Applied Research Corp.)
The Whole Sun Month (WSM) campaign coordinated many ground-based and space-based instruments to look at a full rotation (August 10 - September 8, 1996) of the solar minimum corona. One of the main goals of the campaign was to study and quantify the large-scale physical properties (i.e. densities, temperatures, velocities, and magnetic field) in the solar minimum corona between 1 and 3 solar radii. In order to begin to address this goal, we have picked a subset of the WSM dataset, centered on the West limb as observed on August 17, 1996. We chose this part of the rotation to study because coronagraph images and magnetograms indicate that there is little variation of the equatorial streamer structure with longitude for 45 degrees on either side of this day. Thus, it is appropriate to model this streamer structure with azimuthally symmetric models. We quantify electron density, temperature and magnetic field for this structure, using white light images from LASCO and Mauna Loa, and magnetogram data from MDI and WSO. Additional constraints on the field structure come from EIT images. We use two techniques to calculate the density and temperature and compare the results. The first technique models density using a Van de Hulst inversion and derives temperatures from the density scale heights. The second technique uses the axisymmetric magnetostatic model of Gibson, Bagenal, and Low (JGR, 101, 4813, 1996) to produce density, temperature, and also magnetic field. We compare this modeled magnetic field to one obtained via a potential field extrapolation of the photospheric field.
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