Whitepaper #107 in the Decadal Survey for Solar and Space Physics (Heliophysics) 2024-2033. Main topics: basic research. Additional topics: other basic research; user-need-driven basic space weather research.
Stream Interaction Regions (SIRs), also known as Corotating Interaction Regions (CIRs) play an extremely important role in particle acceleration and transport in the heliosphere. Understanding SIRs is important to fundamental understanding of particle acceleration and better space weather predictions.