Astronomy Letters

, Volume 42, Issue 10, pp 703–712 | Cite as

Two populations of sunspots and secular variations of their characteristics

  • Yu. A. NagovitsynEmail author
  • A. A. Pevtsov
  • A. A. Osipova
  • A. G. Tlatov
  • E. V. Miletskii
  • E. Yu. Nagovitsyna


We investigate the magnetic fields and total areas of mid- and low-latitude sunspots based on observations at the Greenwich and Kislovodsk (sunspot areas) and Mount Wilson, Crimean, Pulkovo, Ural, IMIS, Ussuriysk, IZMIRAN, and Shemakha (magnetic fields) observatories. We show that the coefficients in the linear form of the dependence of the logarithm of the total sunspot area S on its maximum magnetic field H change with time. Two distinct populations of sunspots are identified using the twodimensional H–log S occurrence histogram: small and large, separated by the boundaries log S = 1.6 (S = 40 MSH) and H = 2050 G. Analysis of the sunspot magnetic flux also reveals the existence of two lognormally distributed populations with the mean boundary between them Φ = 1021 Mx. At the same time, the positions of the flux occurrence maxima for the populations change on a secular time scale: by factors of 4.5 and 1.15 for small and large sunspots, respectively. We have confirmed that the sunspots form two physically distinct populations and show that the properties of these populations change noticeably with time. This finding is consistent with the hypothesis about the existence of two magnetic field generation zones on the Sun within the framework of a spatially distributed dynamo.


Sun solar activity magnetic field 


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  1. 1.
    J. M. Beckers and E.H. Schröter, Solar Phys. 10, 384 (1969).ADSCrossRefGoogle Scholar
  2. 2.
    T. J. Bogdan, P. A. Gilman, I. Lerche, and R. Howard, Astrophys. J. 327, 451 (1988).ADSCrossRefGoogle Scholar
  3. 3.
    A. Brandenburg, Astrophys. J. 625, 539 (2005).ADSCrossRefGoogle Scholar
  4. 4.
    R. J. Bray and R. E. Loughhead, Sunspots (Chapman and Hall, London, 1964).Google Scholar
  5. 5.
    J. W. Broxon, Phys. Rev. 62, 508 (1942).ADSCrossRefGoogle Scholar
  6. 6.
    I.-H. Cho, K.-S. Cho, S.-C. Bong, E.-K. Lim, R.-S. Kim, S. Choi, Y.-H. Kim, and V. Yurchyshyn, Astrophys. J. 811, 49 (2015).ADSCrossRefGoogle Scholar
  7. 7.
    G. E. Hale and S. B. Nicholson, Magnetic Observations of Sunspots, 1917–1924, Papers of the Mt. Wilson Observ., Vol. 5 (Carnegie Inst.,Washington, 1938).Google Scholar
  8. 8.
    J. Houtgast and A. van Sluiters, Bull. Astron. Instit. Netherl. 10, 325 (1948).ADSGoogle Scholar
  9. 9.
    C. Kiess, R. Rezaei, and W. Schmidt, Astron. Astrophys. 565, 52 (2014).ADSCrossRefGoogle Scholar
  10. 10.
    Yu. V. Linnik, Method of Least Squares and Principles of the Theory of Observations (Fizmatlit, Moscow, 1962; Pergamon, Oxford, 1961).Google Scholar
  11. 11.
    W. Livingston, J. W. Harvey, O. V. Malanushenko, and L. Webster, Solar Phys. 239, 41 (2006).ADSCrossRefGoogle Scholar
  12. 12.
    W. Livingston, M. J. Penn, and L. Svalgaard, Astrophys. J. Lett. 757, L8 (2012).ADSCrossRefGoogle Scholar
  13. 13.
    W. Mattig, Z. Astrophys. 31, 273 (1953).ADSGoogle Scholar
  14. 14.
    A. Munoz-Jaramillo, R. R. Senkpeil, J. C. Windmueller, E. C. Amouzou, D.W. Longcope, A. G. Tlatov, Y. A. Nagovitsyn, A. A. Pevtsov, G. A. Chapman, A. M. Cookson, A. R. Yeates, F. T. Watson, L. A. Balmaceda, E. E.DeLuca, and P. C.H. Martens, Astrophys. J. 800, 48 (2015).ADSCrossRefGoogle Scholar
  15. 15.
    Yu. A. Nagovitsyn, V. V. Makarova, E. Yu. Nagovitsyna, Solar Syst. Res. 41, 81 (2007).ADSCrossRefGoogle Scholar
  16. 16.
    Yu. A. Nagovitsyn, A. A. Pevtsov, and W. Livingston, Astrophys. J. Lett. 758, L20 (2012).ADSCrossRefGoogle Scholar
  17. 17.
    Yu. A. Nagovitsyn, K. Georgieva, A. A. Osipova, and A. I. Kuleshova, Geomagn. Aeron. 55, 1081 (2015).ADSCrossRefGoogle Scholar
  18. 18.
    S. B. Nicholson, Astron. Soc. Pacif. 45, 51 (1933).ADSCrossRefGoogle Scholar
  19. 19.
    M. J. Penn and W. Livingston, Astrophys. J. 649, L45 (2006).ADSCrossRefGoogle Scholar
  20. 20.
    A. A. Pevtsov, Y. A. Nagovitsyn, A. G. Tlatov, and A. L. Rybak, Astrophys. J. Lett. 42, L36 (2011).ADSCrossRefGoogle Scholar
  21. 21.
    A. A. Pevtsov, L. Bertello, A. G. Tlatov, A. Kilcik, Y. A. Nagovitsyn, and E. W. Cliver, Solar Phys. 289, 593 (2014).ADSCrossRefGoogle Scholar
  22. 22.
    R. Rezaei, C. Beck, and W. Schmidt, Astron. Astrophys. 541, A60 (2012).ADSCrossRefGoogle Scholar
  23. 23.
    R. Rezaei, C. Beck, A. Lagg, J. M. Borrero, W. Schmidt, and M. Collados, Astron. Astrophys. 578, A43 (2015).ADSCrossRefGoogle Scholar
  24. 24.
    T. S. Ringnes, Astrophys. Norveg. 10, 27 (1965).ADSGoogle Scholar
  25. 25.
    T. S. Ringnes and E. Jensen, Astrophys. Norveg. 7, 99 (1960).ADSGoogle Scholar
  26. 26.
    T. A. Schad, Solar Phys. 289, 1477 (2014).ADSCrossRefGoogle Scholar
  27. 27.
    O. Steen and P. Maltby, Astrophys. Norveg. 6, 263 (1960).ADSGoogle Scholar
  28. 28.
    V. E. Stepanov and S. I. Gopasyuk, Izv. Krymsk. Astrofiz. Observ. 28, 194 (1962).Google Scholar
  29. 29.
    A. G. Tlatov and A. A. Pevtsov, Solar Phys. 289, 1143 (2014).ADSCrossRefGoogle Scholar
  30. 30.
    K. A. Tlatova, V. V. Vasil’eva, and A. A. Pevtsov, Geomagn. Aeron. 55, 896 (2015).ADSCrossRefGoogle Scholar
  31. 31.
    A. Wittmann, Solar Phys. 36, 29 (1974).ADSCrossRefGoogle Scholar

Copyright information

© Pleiades Publishing, Inc. 2016

Authors and Affiliations

  • Yu. A. Nagovitsyn
    • 1
    • 2
    Email author
  • A. A. Pevtsov
    • 3
  • A. A. Osipova
    • 1
  • A. G. Tlatov
    • 1
  • E. V. Miletskii
    • 1
  • E. Yu. Nagovitsyna
    • 1
  1. 1.Pulkovo Astronomical ObservatoryRussian Academy of SciencesSt. PetersburgRussia
  2. 2.St. Petersburg State University of Aerospace InstrumentationSt. PetersburgRussia
  3. 3.National Solar ObservatorySunspotUSA

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