On the Differences in Element Abundances of Energetic Ions from Corotating Events and from Large Solar Events
Abstract
The abundances of energetic ions accelerated from high-speed solar wind streams by shock waves formed at corotating interaction regions (CIRs) where high-speed streams overtake the lower-speed solar wind are examined. The observed element abundances appear to represent those of the high-speed solar wind, unmodified by the shock acceleration. These abundances, relative to those in the solar photosphere, are organized by the first ionization potential (FIP) of the ions in a way that is different from the FIP effect commonly used to describe differences between abundances in the solar photosphere and those in the solar corona, solar energetic particles (SEPs), and the low-speed solar wind. In contrast, the FIP effect of the ion abundances in the CIR events is characterized by a smaller amplitude of the differences between high-FIP and low-FIP ions and by elevated abundances of He, C, and S.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- November 1991
- DOI:
- 10.1086/186209
- Bibcode:
- 1991ApJ...382L..43R
- Keywords:
-
- Abundance;
- Solar Cosmic Rays;
- Solar Wind;
- Corotation;
- Galactic Cosmic Rays;
- Ion Charge;
- Particle Acceleration;
- Solar Corona;
- Solar Physics;
- COSMIC RAYS: ABUNDANCES;
- SUN: ABUNDANCES;
- SUN: CORONA;
- SUN: SOLAR WIND