2009/09/22 by Franck Plunian, Graeme R. Sarson, Graeme Sarson +1
Biochemistry, Genetics and Molecular Biology · Physics and Astronomy · #Astro and Planetary Science #Astrophysics #Convection #Convection zone #Geomagnetism and Paleomagnetism Studies #Intermittency #Magnetic field #Magnetic flux #Mechanics #Physics #Solar and Space Plasma Dynamics #Solar cycle #Solar minimum #Solar wind #Stars #Sunspot #Turbulence #astro-ph.SR
paper · pdf · doi:10.1111/j.1745-3933.2009.00760.x
5 pages, 6 figures, accepted for publication in MNRAS Letters
arxiv created 2009/09/22 · openalex publication_date 2009/10/07 · arxiv updated 2015/05/14 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Abstract It is generally believed that sunspots are the emergent part of magnetic flux tubes in the solar interior. These tubes are created at the base of the convection zone and rise to the surface due to their magnetic buoyancy. The motion of plasma in the convection zone being highly turbulent, the surface manifestation of sunspots may retain the signature of this turbulence, including its intermittency. From direct observations of sunspots, and indirect observations of the concentration of cosmogenic isotopes 14C in tree rings or 10Be in polar ice, power spectral densities in frequency are plotted. Two different frequency scalings emerge, depending on whether the Sun is quiescent or active. From direct observations we can also calculate scaling exponents. These testify to a strong intermittency, comparable with that observed in the solar wind.