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Higher order correlations for fluctuations in the presence of fields

A. Boer·S. Dumitru
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Abstract

The higher order moments of the fluctuations for the thermodynamical systems in the presence of fields are investigated in the framework of a theoretical method. The metod uses a generalized statistical ensemble consonant with the adequate expression for the generalized internal energy. The applications refer to the case of a system in magnetoquasistatic field. In the case of linear magnetic media one finds that for the description of the magnetic induction fluctuations the Gaussian approximation is good enough. For nonlinear media the coresponding fluctuations are non-Gaussian, they having a non-null asymmetry. Aditionally the respective fluctuations have characteristics of leptokurtic, mesokurtic and platykurtic type, depending of the value of the magnetic field strength comparatively with a scaling factor of the magnetization curve.

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A. Boer, S. Dumitru. 2002-01-21. Higher order correlations for fluctuations in the presence of fields. https://doi.org/10.1103/physreve.66.046116

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