3. Case study observations and results
This study uses simultaneous chorus, microburst, and electron flux
observations made from 5 December 2017 00:00 UT to 6 December 2017 06:00
UT. Geomagnetic activity prior to December 5th was
relatively low until a weak (Dst ~ -45 nT) storm late on
December 4th. This was accompanied by enhanced
electron fluxes, as observed on MagEIS, in association with substorm
activity (peaks in AE from 600 to 900 nT), which continued for several
days. After December 6th, there was a gradual
recovery, with no storms for the next few days.
There were four magnetic conjunction events (with RBSP and FIREBIRD
within 1 MLT and 1 L shell of each other on 5 December 2017) during
which FIREBIRD obtained high resolution data. Since we focus on the
overall extent of the microburst-producing chorus source region, we
include observations taken throughout the interval of interest. RBSP and
Arase made multiple passes through the dawn-to-dusk MLT sectors across
noon. FIREBIRD and AC6-A also made multiple microburst observations in
these same regions.