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Onset detection | Bays | FAC Location | Validity

(2) Measuring the 'bays'

Now we can look at the data from a selection of SAMNET stations at this time and attempt to characterise the 'bays' or deflections in H and D which are coincident with the Pi2 onset.


Black line: smoothed data; Red line: linear fit to onset bay; Blue line: data bandpass filtered between 20-200 seconds to show Pi2 activity.

H Summary D Summary

The deflections measured by the linear fit to the first 4 minutes of the bays can be plotted and compared with the expected longitudinal variation obtained from an idealised 'substorm current wedge'. This can yield an estimate of the location of the Substorm Current Wedge with respect to the SAMNET array.


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