Levy-stable probability distribution of magnetic field fluctuations at Terra Nova Bay (Antarctica)

The probability distribution functions (PDFs) of short time-scale magnetic field fluctuations were evaluated for Terra Nova Bay (TNB) data, relative to December 1993-January 1994. It is found that short-time field fluctuations are not Gaussian distributed. An anomalous scaling of the probability of return P(0) is found for the smaller scales, and is connected to a Levy regime. Moreover, we discuss the "Levy stable" character of the magnetic fluctuations probability distribution function (PDF) as due to an anomalous diffusion process of magnetospheric plasma. The relevance of these observations for the understanding of magnetospheric plasma transport processes and ionospheric dynamo is pointed out.