Magnetic power spectra derived from ground and space measurements of the solar magnetic fields

V. Abramenko, V. Yurchyshyn, Haimin Wang, P. R. Goode

Research output: Contribution to journalArticlepeer-review

37 Scopus citations

Abstract

We study magnetic power spectra of active and quiet regions by using Big Bear Solar Observatory and SOHO/MDI measurements of longitudinal magnetic fields. The MDI power spectra were corrected with Gaussian Modulation Transfer Function. We obtained reliable magnetic power spectra in the high wave numbers range, up to k = 4.6 Mm-1, which corresponds to a spatial scale l = 1.4 Mm. We find that the occurrence of the spectral discontinuity at high wave numbers, k ≥ 3 Mm-1, largely depends on the spatial resolution of the data and it appears at progressively higher wave numbers as the resolution of the data improves. The spectral discontinuity in the raw spectra is located at wave numbers about 3 times smaller than wave numbers, corresponding to the resolution of the data, and about 1.5-2.0 times smaller in the case of the noise- and-resolution corrected spectra. The magnetic power spectra for active and quiet regions are different: active-region power spectra are described as ∼ k-1.7, while in a quiet region the spectrum behaves as ∼ k-1.3. We suggest that the difference can be due to small-scale dynamo action in the quiet-Sun photosphere. Our estimations show that the dynamo can generate more than 6% of the observed magnetic power.

Original languageEnglish (US)
Pages (from-to)225-240
Number of pages16
JournalSolar Physics
Volume201
Issue number2
DOIs
StatePublished - 2001

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Space and Planetary Science

Fingerprint

Dive into the research topics of 'Magnetic power spectra derived from ground and space measurements of the solar magnetic fields'. Together they form a unique fingerprint.

Cite this