Nicholas L. Bunch

Chorus probability and wave power distributions as observed by the Polar Plasma Wave Instrument

Determining the global distribution of chorus wave power in the off-equatorial region is a crucial component in understanding the contribution of chorus to radiation belt acceleration and loss. In this study we employ a database of chorus observations from the Plasma Wave Instrument (PWI) Sweep Frequency Receiver (SFR) onboard the Polar spacecraft, which are used to generate probability statistics, and approximate typical magnetic wave power as a function of space and geomagnetic activity. Previous studies concerning chorus wave power statistics have focused on a band-integrated and time-averaged data product which is typically used as the fundamental chorus input to radiation belt diffusion models. We estimate this quantity by which mean magnetic wave power and occurrence probability are incorporated to determine what we call “composite” wave power. These data products are a crucial step forward in understanding the radiation belt wave environment and evaluating essential inputs for radiation belt models.