Ion Acceleration and Wave-Particle Interaction at the Interplanetary Shocks Associated with the Halloween 2003 and the 20 January 2005 Events: SOHO/HSTOF, SOHO/EPHIN, and ACE/MAG Observations.

We analyze suprathermal and energetic ions associated with three large coronal mass ejection events during the two most active time periods in the declining phase of this solar cycle. The CMEs and associated flares were observed on Nov. 2 and Nov. 4, 2003 (Halloween events) and on January 20, 2005, by SOHO/LASCO and SOHO/EIT. The second event was accompanied by the largest flare (X28) ever observed. In particular, we focus our study on the upstream regions of the interplanetary shocks driven by these CMEs. By combining data of HSTOF and EPHIN we are able to analyze the ions in a large energy range. HSTOF measures H, He, CNO, and Fe ions in the energy range from 80 keV/e up to 100 MeV/e (for heavy ions). The EPHIN sensor detects protons and the helium isotopes in the energy range 4 to 53 MeV/amu. The temporal evolution of the spectra is resolved in steps of 2 hours corresponding to a spatial resolution in the solar wind frame of 0.02 AU. We compare these results to those associated with the Bastille Day event in 2000, and discuss them in the context of models based of quasi-linear theory of ion acceleration and wave-particle interaction at interplanetary traveling shocks.