HR: 14:15h
AN: SM33E-03 INVITED     [Abstracts]
TI: A Nonequilibrium Statistical Thermodynamics Approach to Non-Gaussian Statistics in Space Plasmas.
AU: * Consolini, G
EM: consolini@ifsi.rm.cnr.it
AF: Ist. Fisica Spazio Interplanetario, INAF, Via del Fosso del Cavaliere, 100, Roma, I-00133 Italy
AB: One of the most interesting aspect of magnetic field and plasma parameters fluctuations is the non-Gaussian shape of the Probability Distribution Functions (PDFs). This fact along with the occurrence of scaling features has been read as an evidence of intermittency. In the past, several models have been proposed for the non-gaussianity of the PDFs (Castaign et al., 1990; Frisch, 1996; Frisch & Sornette, 1997; Arimitsu & Arimitsu, 2000; Beck, 2000; Leubner & Vörös, 2005). Recently, by introducing the concept of randomized operational temperature Beck & Cohen proposed the concept of superstatistics (Beck & Cohen, 2003; Beck, 2004) as the origin of non-Gaussian PDFs in nonequilibrium, long-range correlated, systems. Here, the origin of non-Gaussian PDFs in space plasmas is discussed in the framework of composite thermodynamic systems starting from the idea of randomized operational temperature and using the concept of Lèvy transformation. This approach is motivated by recent theoretical and experimental evidences of multiscale magnetic and plasma structures in space plasmas (Chang, 1999; Chang et al, 2004). A novel shape of the small-scale PDFs is derived and compared with PDFs computed by magnetic field measurements in space plasmas.
DE: 3265 Stochastic processes (3235, 4468, 4475, 7857)
DE: 4430 Complex systems
DE: 4468 Probability distributions, heavy and fat-tailed (3265)
DE: 7839 Nonlinear phenomena (4400, 6944)
DE: 7863 Turbulence (4490)
SC: SPA-Magnetospheric Physics [SM]
MN: Fall Meeting 2005