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Paper: First Results from UVCS: Dynamics of the Extended Corona
Volume: 118, First Advances in Solar Physics Euroconference: Advances in the Physics of Sunspots
Page: 273
Authors: Antonucci, E.; Noci, G.; Kohl, J. L.; Tondello, G.; Huber, M. C. E.; Giordano, S.; Benna, C.; Ciaravella, A.; Fineschi, S.; Gardner, L. D.; Martin, R.; Michels, J.; Naletto, G.; Nicolosi, P.; Panasyuk, A.; Raymond, C. J.; Romoli, M.; Spadaro, D.; Strachan, L.; van Ballegooijen, A.
Abstract: The Ultraviolet Coronagraph Spectrometer (UVCS) started to observe the Sun at the end of January 1996. Here we present a selection of results obtained with the UVCS in the first months of operation. UV spectral line profiles in coronal holes, and in general in regions with open magnetic field lines, are much broader than in closed field line regions; that is, line-of-sight velocities are much larger in open field lines . Polar plumes have narrower profiles than interplume regions. The O VI ratio diagnostics indicates that in polar coronal holes the outflow velocity is progressively increasing with heliodistance and exceeds 100 km/sec near 2--2.5 solar radii. A coronal mass ejection observation has revealed line--of--sight plasma motions of 100 km/sec and a complex dynamics.
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