The STEREO/HET Electron Event List Notes

A. Labrador, Caltech
Last updated 9/7/23

The STEREO/HET Ahead and Behind event lists are generated from the 0.7-1.4 MeV 1 hour average intensities, available in the ASCII data files at the HET Data and Plots pages here. The event-logging code scans through this intensity data linearly.

For an event to be logged,

• The intensity must exceed a threshold (0.05 particles/cm^2 s sr MeV)
• The intensity must exceed this threshold for at least 3 points. Note that this is points, not hours, as some time periods have skips.
• The start of the event is the first point above threshold.
• The event continues as long as the points are above threshold.
• The end of the event is the last point above threshold.
• If the event length exceeds 0.2 days (~4.8 hours), its plot is saved and linked from the .html lists and the .csv file.
• If the event length exceeds 12 points above minimum, it is defined as a "long" event.
• After a long event, the next event must exceed 12 points above threshold (instead of 3). After 12 points beyond the end of the last long event, the points above threshold minimum is returned to 3. The purpose of this long event threshold, short event filter, is to reduce the long tails of some events bouncing above and below threshold from counting as multiple small events.