Authors: Yuliang Ding(EPSS, UCLA), Chen Shi(EPSS, UCLA), Marco Velli(EPSS, UCLA), Zesen Huang(EPSS, UCLA), Nikos Sioulas(JPL)

A superposed-epoch analysis is carried out to study the turbulence properties near the Corotating Interaction Regions (CIRs), with the zero epoch defined by Minimum Variance Analysis (MVA). Over 200 CIR events are selected and the data source includes OMNI2, ACE and WIND. We calculated the superposed median of normalized residual energy (sigmar) and normalized cross helicity (sigmac), to understand the change of magnetic field energy, velocity energy, outward and inward alfvenic energy near CIRs. Our results showed that there is a spike in sigmar and a drop in sigmac at zero epoch, which is consistent to our previous simulation.