Pi 1 pulsations

Pi1 are irregular ULF range (T = 1 - 40 s) magnetic pulsations that can be divided into two groups, Pi1 B and Pi C, i.e., into burst like and continuous (Heacock, 1967). There are two maxima in the occurrence rate, on midnight and on pre-noon. The midnight pulsations contain both Pi1 B and Pi C flavours, while the prenoon pulsations are all of continuous type.

References

• Heacock, R. R., Two subtypes of Pi micropulsations, J. Geophys. Res., 72, 3905, 1967.
• Higuchi, Y., Pi 1 magnetic pulsations observed in association with low latitude aurora, J. Geomag. Geoelectr., 46, 177-192, 1994.

See also:

• Space Physics Text Book of Oulu