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Energetic electron precipitation (EEP) associated with pulsating aurora can transfer greater than 30 keV electrons from the outer radiation belt region into the upper atmosphere and can deplete atmospheric ozone via collisions that produce NOx and HOx molecules. Our knowledge of exactly how EEP occurs is incomplete. Previous studies have shown that pitch angle scattering between electrons and lower‐band chorus waves can cause pulsating aurora associated with EEP and that substorms play an important role. In this work, we quantify the timescale of chorus wave decay following substorms and compare that to previously determined timescales. We find that the chorus decay e‐folding time varies based on magnetic local time (MLT), magnetic latitude, and wave frequency. The shortest timescales occur for lower‐band chorus in the 21 to 9 MLT region and compares, within uncertainty, to the energetic pulsating aurora timescale of Troyer et al. (2022,https://doi.org/10.3389/fspas.2022.1032552) for energetic pulsating aurora. We are able to further support this connection by modeling our findings in a quasi‐linear diffusion simulation. These results provide observations of how chorus waves behave after substorms and add additional statistical evidence linking energetic pulsating aurora to substorm driven lower‐band chorus waves.

We extend our database of whistler mode chorus, based on data from seven satellites, by including ∼3 years of data from Radiation Belt Storm Probes (RBSP)‐A and RBSP‐B and an additional ∼6 years of data from Time History of Events and Macroscale Interactions during Substorms (THEMIS)‐A, THEMIS‐D, and THEMIS‐E. The new database allows us to probe the near‐equatorial region in detail, revealing new features. In the equatorial source region, |λ_m|<6°, strong wave power is most extensive in the 0.1–0.4f_cebands in the region 21–11 magnetic local time (MLT) from the plasmapause out toL^∗ = 8 and beyond, especially near dawn. At higher frequencies, in the 0.4–0.6f_cefrequency bands, strong wave power is more tightly confined, typically being restricted to the postmidnight sector in the region 4<L^∗<6. The global distribution of strong chorus wave power changes dramatically with increasing magnetic latitude, with strong chorus waves in the region 12<|λ_m|<18° predominantly observed at frequencies below 0.3f_cein the prenoon sector, in the region 5<L^∗<8.