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Session 8 - Corona III.
Oral session, Saturday, June 28
Ballroom A, Chair: Barry LaBonte
SUMER (Solar Ultraviolet Measurements of Emitted Radiation) line profiles above the limb in coronal holes are important for constraining thermodynamic models governing the outflow of the solar wind. Observational constraints in terms of thermal and nonthermal velocities, and upper limits on wave velocity amplitudes can be directly compared with in-situ observations. We present new observations of line profiles in polar plumes, and inter-plume regions, above the limb in coronal holes obtained with the SUMER instrument on the SOHO spacecraft. Detailed structure can be seen extending beyond 1.5 solar radii (out to the edge of the SUMER field-of-view), with intensities in the plume regions roughly 10-50% brighter than the inter-plume regions, but line widths in the plumes roughly 10% narrower than the inter-plume regions. Possible explanations for this observed anti-correlation between line width and intensity, and the correspondence with observed in-situ solar wind signatures will be discussed.
Program listing for Saturday