Turbulent magnetic energy spectrum and the cancellation function of solar photospheric magnetic fields

G. Marschalkó, K. Petrovay

Research output: Contribution to journalArticle

Abstract

A simple analytical relation of form α = 2κ - 1 between the magnetic energy spectral exponent α of the turbulent magnetic field in the solar photosphere and its magnetic flux cancellation exponent κ, valid under certain restrictive assumptions, is tested and extended outside its range of validity in a series of Monte Carlo simulations. In these numerical tests artificial "magnetograms" are constructed in 1D and 2D by superposing a discrete set of Fourier modes of the magnetic field distribution with amplitudes following a power law spectrum and measuring the cancellation function on these simulated magnetograms. Our results confirm the validity of the analytical relation and extend it to the domain α <-1 where κ → 0 as α → -∞. The observationally derived upper limit of 0.38 on κ implies α <-0.24 in the granular size range, apparently at odds with a small scale dynamo driven in the inertial range.

Original languageEnglish
Pages (from-to)952-955
Number of pages4
JournalAstronomische Nachrichten
Volume334
Issue number9
DOIs
Publication statusPublished - Nov 2013

Fingerprint

solar magnetic field
magnetic signatures
cancellation
energy spectra
exponents
magnetic field
photosphere
magnetic fields
range size
energy
magnetic flux
power law
simulation
distribution
test
measuring

Keywords

  • Magnetohydrodynamics (MHD)
  • Sun: atmosphere
  • Sun: magnetic fields
  • Turbulence

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

Turbulent magnetic energy spectrum and the cancellation function of solar photospheric magnetic fields. / Marschalkó, G.; Petrovay, K.

In: Astronomische Nachrichten, Vol. 334, No. 9, 11.2013, p. 952-955.

Research output: Contribution to journalArticle

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