On the Lyman #alpha# and O Viline Profiles in Streamers and Coronal Holes

摘要

The profiles of the Ly#alpha# line at 1215.6 A and of the O VI doublet at 1031.9 A and 1037.6 A in the extended solar corona have been analyzed vs. latitude and radial direction, performing observations with the Ultraviolet Coronagraph Spectrometer (UVCS) on board the ESA-NASA solar satellite SOHO (Solar and Heliospheric Observatory). The results show that these lines behave differently region and narrower values towards the pole, while the FWHM of O VI lines has a minimum at the center of the streamer and slightly increases towards the polar regions. We briefly discuss the impact of the results on coronal heating theories.