Eur. Phys. J. Special Topics 174, 219-228 (2009)
https://doi.org/10.1140/epjst/e2009-01102-y

A study of non-extensivity in the Earth's magnetosphere

¹ Institute for Space Applications and Remote Sensing, National Observatory of Athens, Metaxa and Vas. Pavlou St., Penteli, 15236 Athens, Greece
² Section of Solid State Physics, Department of Physics, University of Athens, Panepistimiopolis, Zografos, 15784 Athens, Greece

Corresponding author: gbalasis@space.noa.gr

Abstract

Magnetic storms are undoubtedly among the most important phenomena in space physics and also a central subject of space weather. The non-extensive Tsallis entropy has been recently introduced, as an effective complexity measure for the analysis of the geomagnetic activity D_st index. Tsallis entropy has been shown to sensitively detect the complexity dissimilarity between pre-storm activity and intense magnetic storms in the Earth's magnetosphere. Here, we show that the D_st time series obey a modified form of the Gutenberg-Richter law for the case of non-extensive statistics, thus providing evidence for universality in magnetic storm and earthquake occurrence.