Abundances and energy spectra of corotating interaction region heavy ions

We have surveyed He-Fe spectra for 41 Corotating Interaction Regions (CIRs) from 1998-2007 observed on ACE. The spectra are similar for all species, and have the form of broken power laws with the spectral break occurring at a few MeV/nucleon. Except for overabundances of He and Ne, the abundances are close to those of the solar wind. We find the rare isotope 3 He is enhanced in similar to 40% of the events. In individual CIRs the Fe/O ratio correlates strongly with the solar wind Fe/O ratio measured 2-4 days prior to the CIR passage. Taken together with previously reported observations of pick-up He in CIRs, these observations provide evidence that CIRs are accelerated out of a suprathermal ion pool of heated solar wind ions, pick-up ions, and remnant suprathermal ions from impulsive solar energetic particle (SEP) events.