I am analyzing data from an instrument that measures low energy electron flux at Geo-Stationary orbit. There are sharp oscillations in the particle flux of 30 eV electrons occurring from about noon to 8 pm (space-craft local). The period of this activity is relatively consistent at about one cycle every 13 minutes. I am trying to determine if this is a natural phenomenon or systemic contamination.
EDIT: I have added a plot of data containing the oscillations. The Y-axis represents counts per interval and X axis is time. The purple line represents the south-most zone and the red the north-most. I have intentionally removed the title/legend/labels. The oscillations are obvious in the right side of the plot.
My question is this:
Are there any natural cycles within the solar-wind or radiation belts that have a similar frequency?
A second question:
Are there evenly spaced and distinct longitudes containing higher densities of electron cycling that the space-craft might be passing through?
Any other ideas as to the cause of the oscillation are welcome.