Enhanced solar wind He-3(2+) associated with Coronal Mass Ejections

Using data from the MASS high-resolution solar wind spectrometer on the WIN D spacecraft, six enhanced He-3(2+)/He-4(2+) periods were identified from J anuary 1995 to May 1998. The ratios observed in these events are four to te n times higher than previously reported average solar wind values. All enha nced He-3(2+) periods were associated with the passage of CME-ejecta. The o bserved time periods were either within but towards the end of the CME-asso ciated magnetic clouds or trailing the magnetic cloud by about 24 hours. Al l the enhanced He-3(2+) periods have a mixture of low (cold) iron charge st ates along with high (hot) oxygen charge states. The unusual charge state c omposition of these enhanced He-3(2+) events suggests the plasma came from a relatively cold and dense solar region, or from a rapidly expanding plasm a parcel in the corona. We suggest that the enhanced He-3(2+) plasma origin ated from the prominence core embedded within the CME.