Comparison between average charge states and abundances of ions in CMEs and the slow solar wind

Abstract

We present results from a comparison of CME and slow solar wind ejecta detected at the ACE spacecraft in 1998 and 1999. CME events were identified based on the observation of counterstreaming halo electrons from SWEPAM data. We discuss the compositional signatures in the framework of a recent model of the coronal magnetic field by Fisk and Schwadron [1]. We conclude that slow solar wind and CMEs have a common source in the corona, presumably coronal loops. The largest amount of fractionation is found in helium and in charge state composition. The former is related to collisional effects in the corona and the latter is attributed to the anomalous heating and propagation properties of some CMEs. © 2001 American Institute of Physics.