Magnesium Isotopic Abundance In Slow And Coronal Hole Associated Solar Wind: SOHO/CELIAS/MTOF Measurements.
Abstract
The solar wind provides the most comprehensive source of information about solar isotopic abundance. The flow dynamic of the solar wind is determined by the magnetic topology of the flux tubes. The slow solar wind originating from closed field line regions, has a slow bulk velocity and high freeze-in temperature, and the high speed solar wind which has a low freeze-in temperature and originates from open flux tubes in coronal holes. In situ solar wind measurements provide therefore important informations on the present-day isotopic composition of the outer convective zone of the Sun. Data from the high resolution Mass Time-of-Flight spectrometer MTOF and the Charge Time-Of-Flight spectrometer on board SOHO have been accumulated for time periods in which coronal hole or non-coronal hole type plasma has been detected in order to investigate the abundance ratios of magnesium isotopes originating from these two different source regions of the solar wind in the context of isotope fractionation.
- Publication:
-
8th SOHO Workshop: Plasma Dynamics and Diagnostics in the Solar Transition Region and Corona
- Pub Date:
- October 1999
- Bibcode:
- 1999ESASP.446..395K