Investigating the Timescales of Substorm Driven Chorus and the Connection to Pulsating Aurora

The energetic particle precipitation (EPP) associated with pulsating aurora is likely a significant contributor to electron losses in the radiation belt. These radiation belt electrons can have dramatic impacts on our atmosphere ranging from the dynamic blinking patches of pulsating aurora to ozone depletion. Connecting atmospheric effects to mechanisms in the radiation belts is challenging, but important to understand magnetosphere-ionosphere coupling. One possible way of approaching this problem is through a statistical timescale. Meredith et. al (2000) found that injection driven chorus waves decayed with a timescale of around 1 hour following injection. Troyer et. al (2022) found that pulsating aurora energy content hardness decreases significantly around 1 hour following substorm onset. Given that chorus waves are a known mechanism for pulsating aurora, could these two findings be related? Here we investigate this possible timescale connection further. We do this by using EMFISIS measurements from the Van Allen Probes to observe chorus wave intensity decay and by using riometers to measure ionospheric changes through EPP-induced cosmic noise absorption.