Magnetic pattern at supergranulation scale: the Void Size Distribution
arXiv:1406.5871 · doi:10.1051/0004-6361/201424026
Abstract
The large-scale magnetic pattern of the quiet sun is dominated by the magnetic network. This network, created by photospheric magnetic fields swept into convective downflows, delineates the boundaries of large scale cells of overturning plasma and exhibits voids in magnetic organization. Such voids include internetwork fields, a mixed-polarity sparse field that populate the inner part of network cells. To single out voids and to quantify their intrinsic pattern a fast circle packing based algorithm is applied to 511 SOHO/MDI high resolution magnetograms acquired during the outstanding solar activity minimum between 23 and 24 cycles. The computed Void Distribution Function shows a quasi-exponential decay behavior in the range 10-60 Mm. The lack of distinct flow scales in such a range corroborates the hypothesis of multi-scale motion flows at the solar surface. In addition to the quasi-exponential decay we have found that the voids reveal departure from a simple exponential decay around 35 Mm.
6 pages, 8 figures, to appear in Astronomy and Astrophysics
References in corpus (9)
- Analysis of Quiet-Sun Internetwork Magnetic Fields Based on Linear Polarization Signals
- Mesogranulation and the solar surface magnetic field distribution
- Diffusion of magnetic elements in a supergranular cell
- Inter-Network magnetic fields observed during the minimum of the solar cycle
- Dead calm areas in the very quiet Sun
- The Intensity Profile of the Solar Supergranulation
- Multiscale magnetic underdense regions on the solar surface: Granular and Mesogranular scales
- 3D photospheric velocity field of a Supergranular cell
- Line shape effects on intensity measurements of solar features: Brightness correction to SoHO MDI continuum images