Balloon observations of the extent and structure of auroral-zone electron precipitation events

Simultaneous balloon observations of auroral-zone electron precipitation from College and Fort Yukon, Alaska, in June of 1962 showed examples of the electron influx increasing with increasing geomagnetic latitudes, both with and without magnetic bay disturbances. Under more disturbed conditions, the X-ray flux recorded by the southern balloon far exceeded that by the northern balloon, indicating a sharp boundary for the electron precipitation region as suggested by O'Brien on the basis of satellite measurements.