Bulletin of Taras Shevchenko National University of Kyiv. Astronomy, no. 52, p. 51-56 (2015)

Repeated maxima of sunspot cycles

V. Krivodubskij. Dr. Sci.
Taras Shevchenko National University of Kyiv, Kyiv
Abstract
The explanation for the observed phenomenon of repeated maxima of sunspot cycles is proposed. Key roles in the proposed scenarioplay two tides of toroidal field from the lower base of the solar convection zone (SCZ) to the surface. Deep toroidal field is excited due to Ω-effectnear the bottom of the SCZ at the beginning of the cycle. Then this field is transported to the surface due to combined acting of magnetic buoyancy,magnetic ∇ρ-flow and turbulent diamagnetism in the equatorial domain. Over time the magnetic fragments can be seen as bipolar spots in themiddle latitudes in the “royal zone”. This first wave of toroidal field, which is directed up, gives the main maximum activity spots. However, theunderlying toroidal field in the high-latitude polar domains at the beginning of the cycle is blocked by directed downward magnetic∇ρ-pumping and turbulent diamagnetism. Directed to the equator deep meridional flow replaces this field to the low latitudes (the equatorialdomain) during about 1 – 2 years. After that the turn of floating this “retarded” field to surface (second tide of toroidal field). Coming to the surfaceat low latitudes this second portion of toroidal field leads to second sunspot maximum.

Keywords
Maxima of sunspot cycles

References
Vainshtein, S.Y., Zeldovych, Ia.B., Ruzmaikyn, A.A. 1980, Turbulentnoe dynamo v astrofyzyke
Krauze, F., Rэdler, K-Kh. 1984, Mahnytnaia hydrodynamyka srednykh polei y teoryia dynamo
Stix, M. 1981, Solar. Phys.,74, 79
Rüdiger, G., Arlt R. 2002,The Fluid Mechanics of Astrophysics and Geophysics, 9, 147
Ossendrijver, M. 2003, Astron. Astrophys. Rev.,11, 4, 287
Charbonneau, P. 2010, Living Rev. Solar Phys., 7, 3, 1
Vytynskyi, Iu.Y., Kopetskyi, M., Kuklyn, H.V. 1986, Statystyka piatnoobrazovatelnoi deiatelnosty Solntsa
Gnevyshev, M. N. 1963, Soviet Astronomy,7,3, 311
Antalova, A., Hnevyshev, M.N. 1965, Astron. zhurn.,42, 253
Gnevyshev, M.N. 1967, Solar Phys.,1, 107
Gnevyshev, M.N. 1977, Solar Phys.,51, 175
Ishkov, V.N. 2005, Abstracts of the сonf. “Astronomy and space physics at KyivUniversity”, Kyiv, Ukraine, May 22-26,63
Komm, R.W., Howard, R.F., Harvey, J.W. 1993, Solar Phys.,147, 207
Nesme-Ribes, E., Meunier, N., Vince, I. 1997, Astron. Astrophys.,321, 323
Snodgrass, H.B., Dailey, S.B. 1996, Solar Phys.,163, 21
Hathaway, D.H. 1996, Astrophys. J.,460, 1027
Georgieva, K., Kirov, B. 2011, J. Atmospheric and Solar Terrestrial Physics,73, 2-3, 207
Georgieva, K. 2011, ISRN Astronomy and Astrophysics, 2, ID 437838
Hathaway, D.H., Gilman, P., Harvey, J.W. 1996, Science,272, 1306
Giles, P.M., Duval, T.L.Jr., Scherrer, P.H., Bogart, R.S. 1997, Nature, 390, 52
Braun, D.L., Fan, Y. 1998, Astrophys. J., 508, 105
Braun, D.C., Birc, A.C. 2008, Astrophys. J. Lett.,689, 161
Schou, J., Bogart, R.S. 1998, Astrophys. J. Lett., 504, 131
Haber, D.A., Hindman, B.W., Toomre, J. 2002, Astrophys. J., 570,855
Basu, S., Antia, H.M. 2003, Astrophys. J.,585, 553
Zhao, J., Kosovichev, A.G. 2004, Astrophys. J.,603, 776
Kosovichev, A.G. 2008, Advances in Space Res.,41, 830
Van Ballegooijen, A.A., Choudhuri, A.R. 1988, Astrophys. J.,333,965
Jiang, J., Chatterjee, P., Choudhuri, A. 2007, MNRAS,381,4, 1527
Fisher, G.Y., Fan, J., Longcope, D.W. 2000, Physics of Plasma., 7,5, 2173
Hathaway, D.H., Nandy, D., Wilson, R.M., Reichmann, E.J. 2003, Astrophys. J.,589, 665
Nandy, D., Choudhuri, A.R. 2002, Science,296, 1671
Krivodubskij, V.N. 2005, Astron. Nachr.,326, 1, 61
Drobyshevskij, E.M. 1977, Astrophys. Space Sci.,46, 41
Vainshtein, S.Y. 1983, Mahnytnye polia v kosmose
Stix, M. 2002, The Sun: an introduction, second edition
Kitchatinov, L.L. 1991, Astron. Astrophys.,243, 2, 483

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DOI: https://doi.org/10.17721/BTSNUA.2015.52.51-56