Abstract
We study the effects of two-dimensional turbulence generated in sunspot umbra due to strong magnetic fields and Alfven oscillations excited in sunspots due to relatively weak magnetic fields on the evolution of sunspots. Two phases of sunspot magnetic field decaying are shown to exist. The initial rapid phase of magnetic field dissipation is due to two-dimensional turbulence. The subsequent slow phase of magnetic field decaying is associated with Alfven oscillations. Our results correspond to observed data that provide evidence for two types of sunspot evolution. The effect of macroscopic diamagnetic expulsion of magnetic field from the convective zone or photosphere toward sunspots is essential in supporting the long-term stability and equilibrium of vertical magnetic flux tubes in sunspots.
Similar content being viewed by others
References
S. I. Vainshtein, Magnetic Fields in Space (Nauka, Moscow, 1983) [in Russian].
S. I. Vainshtein, Ya. B. Zel’dovich, and A. A. Ruzmaikin, Turbulent Dynamo in Astrophysics (Nauka, Moscow, 1980) [in Russian].
R. Bray and R. Loughhead, Sunspots (Chapman Hall, London, 1964; Mir, Moscow, 1967).
S. D. Ivanov and V. P. Maksimov, “On Decay of Sunspots,” Pis’ma Astron. Zh. 4, 232–234 (1978).
Ya. B. Zel’dovich, “Magnetic Field at Two-Dimensional Motion of Conducting Liquid,” Zh. Eksp. Teor. Fiz. 31, 154–156 (1956).
F. Krauze and K.-H. Raedler, Mean Field Magnetohydrodynamics and Dynamo Theory (Pergamon, Oxford, 1980; Mir, Moscow, 1984).
V. N. Krivodubskii, “On Turbulent Conductivity and Magnetic Permittivity of Solar Plasma,” Soln. Dannye, No. 7, 99–109 (1982).
V. N. Obridko and R. B. Teplitskaya, “Physical Conditions in Sunspots,” Itogi Nauki Tekh., Ser.: Astron. 14, 7–147 (1978).
V. N. Obridko, V. N. Dashevskii, and O. G. Badalyan, “Temperature Distribution in Heterogeneous Medium with Radiative Equilibrium,” in Physics of the Sun (Nauka, Moscow, 1979), pp. 16–61 [in Russian].
E. Parker, Cosmic Magnetic Fields (Oxford Univ. Press, Oxford, 1979; Mir, Moscow, 1982), Vol. 2 [in Russian].
A. A. Solov’ev, “Ohmic Dissipation of Sunspots,” Astron. Zh. 53, 140–147 (1976).
A. A. Solov’ev, “On Problem of Dissipation of Sunspots,” Soln. Dannye, No. 7, 73–78 (1976).
V. Bumba, “Development of Spot Group Areas in Dependence on the Local Magnetic Field,” Bull. Astron. Inst. Czech. 14, 91–97 (1963).
V. Bumba and R. Howard, “Large-Scale Distribution of Solar Magnetic Fields,” Astrophys. J. 141, 1502–1512 (1965).
T. G. Cowling, “The Sun,” in The Solar System. I, Ed. by G. P. Kuiper (Chicago Univ. Press, Chicago, 1953), p. 532.
V. A. Krat, V. N. Karpinsky, and L. M. Pravdjuk, “On the Sunspot Structure Solar Physics,” Sol. Phys. 26, 305–317 (1972).
F. Krause and G. Rüdiger, “On the Turbulent Decay of Strong Magnetic Fields and the Development of Sunspot Areas,” Sol. Phys. 42, 107–119 (1975).
V. N. Krivodubskij, “Turbulent Dynamo near Tachocline and Reconstruction of Azimuthal Magnetic Field in the Solar Convection Zone,” Astron. Nachr. 326, 61–74 (2005).
F. Meyer, H. U. Schmidt, N. O. Weiss, and P. R. Wilson, “The Growth and Decay of Sunspots,” Mon. Not. R. Astron. Soc. 169, 35–57 (1974).
K.-H. Rädler, “Zur Elektrodynamik turbulent bewegter leitender Medien,” Z. Naturforsch., A: Astrophys., Phys. Phys. Chem. 23, 1841–1860 (1968).
G. Stellmacher and E. Wiehr, “The Deep Layers of Sunspot Umbrae,” Astron. Astrophys. 45, 69–76 (1975).
M. Stix, The Sun (Springer, Berlin, 1989).
A. A. Van Ballegooijen, “The Overshoot Layer at the Base of the Solar Convective Zone and the Problem of Magnetic Flux Storage,” Astron. Astrophys. 113, 99–112 (1982).
Author information
Authors and Affiliations
Corresponding author
Additional information
Original Russian Text © V.N. Krivodubskii, 2012, published in Kinematika i Fizika Nebesnykh Tel, 2012, Vol. 28, No. 5, pp. 37–49.
About this article
Cite this article
Krivodubskii, V.N. Turbulent effects of sunspot magnetic field reconstruction. Kinemat. Phys. Celest. Bodies 28, 232–238 (2012). https://doi.org/10.3103/S0884591312050054
Received:
Published:
Issue Date:
DOI: https://doi.org/10.3103/S0884591312050054