Bibcode
DOI
Sánchez Almeida, J.
Bibliographical reference
The Astrophysical Journal, Volume 657, Issue 2, pp. 1150-1156.
Advertised on:
3
2007
Journal
Citations
16
Refereed citations
14
Description
We derive a first-order linear differential equation describing the
shape of the probability density function (PDF) of magnetic field
strengths in the quiet Sun. The modeling is very schematic. It considers
convective motions which continuously supply and withdraw magnetic
structures. In addition, a magnetic amplification mechanism increases
the field strength up to a threshold that cannot be exceeded. These
three basic ingredients provide PDFs in good agreement with the PDFs
produced by realistic numerical simulations of magnetoconvection, as
well as with quiet-Sun PDFs inferred from observations. In particular,
the distribution is approximately lognormal, and it produces an excess
of magnetic fields (i.e., a hump in the distribution) right before the
maximum field strength. The success of this simple model may indicate
that only a few basic ingredients shape the quiet-Sun PDF. Our approach
provides a concise parametric representation of the PDF, as required to
develop automatic methods of diagnostics.