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Temporal and Spatial Correlation between Chorus Waves and Substorm Electron Precipitation. Using conjugate observations from RBPS and NOAA POES, we want to: Reexamine the temporal and spatial correlation between chorus waves and precipitating ~10s keV electrons.
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Temporal and Spatial Correlation between Chorus Waves and Substorm Electron Precipitation Using conjugate observations from RBPS and NOAA POES, we want to: • Reexamine the temporal and spatial correlation between chorus waves and precipitating ~10s keV electrons. • Quantify the performance of using electron precipitation as the chorus wave proxy. • Explore the connection between proton precipitation and EMIC waves. Yue Chen(Los Alamos National Laboratory) [Chen et al., 2014 GRL] Van Allen Probes SWG Meeting, APL, July 2015
1. Temporal Correlation • Wave (RBSP) and e- (POES) data from same (L, MLT) bins but different altitude. • Clear one-to-one relation between intensified chorus waves and 30keV electron precipitation in the dawn sector . 2/10
2. Temporal Correlation (cont’d) • Clear one-to-one relation between (most) intensified chorus waves and 30keV electron precipitation in the noon sector . 3/10
3. Temporal Correlation (cont’d) • Clear one-to-one relation between (most) intensified chorus waves and 30keV electron precipitation except for the evening sector. 4/10
5. Spatial Correlation (cont’d) • Spatial correlation is confirmed and quantified. 6/10
7. Performance Evaluation (cont’d) • PE for RBSP-A: 0.37; PE for RBSP-B: 0.11 (in comparison, PEs using empirical averaged distributions are ~ -1.2 for both. 8/10
8. One Case EMIC Wave Related to Proton Precipitation Copied from Engerets, et al. [2014] • This case shows the relation between EMIC waves and ring current proton precipitation. • Indicate the possibility of using proton precipitation from LEO as EMIC proxy. 9/10
Summary and Conclusions • We have confirmed the significant one-to-one correlation between intensified chorus waves and precipitation events of substorm events, using conjugate RBSP and NOAA POES observations. • We also statistically demonstrated the significant correlation between chorus waves and substorm electron precipitation during periods with high AE values (>300nT). • Based on the temporal and spatial correlation, it is reasonable to use precipitating electrons as the chorus wave proxy for event-specific chorus wave global distributions, which are more reliable than using statically averaged distributions. • We also present a case showing a similar connection may exist between the EMIC waves and precipitating protons. Acknowledgements: We are grateful for the use of data from NOAA POES MEPT and Van Allen Probes EMFISIS measurements. Thanks are extended to all PIs and data teams. 10/10