Anomalous scaling laws of intensity fluctuations in the solar photosphere*
Dipartimento di Fisica, Università della Calabria, 87036 Rende (CS), Italy Istituto Nazionale per la Fisica della Materia, Unità di Cosenza, Italy
Accepted: 3 August 2001
The photospheric intensity field, obtained from THEMIS-IPM observations, is analysed. We investigate the scaling behavior of intensity fluctuations, following an approach which is used in the study of passive scalar fluctuations in fully turbulent flows. By means of the methods which are applied in the study of multifractal measures, it is shown that the intensity fluctuations are characterised by anomalous scaling laws, identified by defining a dissipation field in analogy with the dissipation of passive scalar fluctuations in fluids. It is shown, finally, that this field is more intermittent in the higher photospheric layers than in the lower ones.
Key words: Sun: photosphere
© ESO, 2001