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Session 1 - Chromosphere, Corona, Flares.
Display session, Friday, June 27
Ballroom B, Chair: Charles Kankelborg

[1.14] Absolute Elemental Abundances in Streamers

J. C. Raymond, J. Kohl, R. Suleiman, A. Ciaravella, S. Fineschi, L. Gardner, A. Panasyuk, L. Strachan (CfA), G. Noci (Universita di Firenze), E. Antonucci (Osservatorio di Torino), P. Nicolosi, G. Naletto (Universita di Padova), S. Giordano, C. Benna (Universita di Torino)

The UVCS instrument aboard the SOHO satellite has measured the intensities of emission lines of H, N, O, Mg, Al, S, Ar, Ca ,Fe and Ni at 1.5 solar radii in a quiescent equatorial helmet streamer and in an active region streamer. The First Ionization Potential (FIP) effect is clearly seen. Low FIP elements show nearly photospheric abundances above the active region and along the edges of the equatorial streamer, while high FIP elements are depleted by a factor of 2-3. Near the center of the streamer, presumably the closed field region, the low-FIP elements are at about 1/3 photospheric abundances, and the high FIP elements are near 1/10 their photospheric values.


Program listing for Friday