Previous abstract Next abstract

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

[1.54] The Coronal Helium Abundance and the Solar Wind

V. H. Hansteen (University of Oslo), D. M. Hassler (Southwest Research Institute), E. Leer (University of Oslo), T. E. Holzer (HAO/NCAR), T. N. Woods (University of Colorado)

The coronal Helium abundance depends on the rate Helium is brought into the corona via the transition region from the chromosphere and on the rate that Helium is removed from the corona in the Solar wind. Recent multi-fluid models of the combined chromosphere, corona, solar wind system show that the corona may have a significant Helium abundance; perhaps even exceeding 50% of the Hydrogen number density. These models also indicate that in order to rerproduce the Solar wind at 1AU ions (\alpha-particles as well as protons) may be required to be the most important recipient of the coronal heating process. In these models the role of electrons in the energetics of the Solar wind is much reduced compared to the standard thermally driven winds. A measurement of the coronal Helium abundance will serve to fix these theoretical ideas and may give important clues as to mixing processes in the chromosphere as well as to coronal heating processes. Consequently, we will discuss the current state of observations (i.e. SOHO), and their limitations, as well as plans for future observations (i.e. sounding rocket, Spartan).

Program listing for Friday