Interplanetary Consequences of Colliding CMEs

Dr. Natchimuthuk Gopalswamy
Laboratory for Extraterrestrial Physics
NASA Goddard Space Flight Center

Colliding CMEs have important implications to a number of physical processes in the near-Sun interplanetary medium: Shock propagation, particle acceleration and solar wind composition. I will use white light images from SOHO and long wavelength radio data from Wind to describe some of the pertinent issues. After a brief assessment of the extent of CME interaction from white light observations, I will discuss what kind of collisions result in electron and proton acceleration. Finally, I will present some statistical results on solar energetic particle events and CME interaction.