Talk abstract

A phenomenological model for fluctuating magnetic fields in the photosphere
K. Petrovay, C.-L. Tian

Abstract

Fluctuating magnetic fields in the solar photosphere are observed to have a patchy distribution on scales of order 10 Mm. This is somewhat puzzling, as a small scale dynamo process, to which these fields are usually attributed, is expected to result in fluctuating fields with a correlation length not exceeding the integral scale of turbulence, which is the granular scale of 1 Mm in the solar case. In order to study the origin of these large spatial scales in the fluctuations, here we consider a phenomenological model of the turbulent field distribution where the small scale dynamo is represented by a source term, while the spatial distribution of the resulting unsigned magnetic energy density is influenced by turbulent diffusion in the strongly inhomogeneous solar plasma.