Abstract
Polar and low-latitude faculae were identified in daily images based on white-light observations from the MDI (1996–2011) and SOHO (2010–2019) space observatories. The boundaries of the faculae were combined with magnetic field observations at the closest possible instant of observation. The time and latitude distributions, as well as other properties of polar and low-latitude faculae, were analyzed. The resulting data on polar faculae were supplemented with observational data from Mitaka Observatory (Japan) for the period of 1951–1999. Thus, we compiled a summary series of polar activity for the period of 1951–2019. The distributions of polar faculae by area and magnetic field intensity are considered. The maximum distribution of the facula area at latitudes above θ > 55° occurs at values of approximately 6–10 mhs. The magnetic field of polar faculae has a maximum of B ~ 70–100 G. The amplitude of polar activity at the minimum in the 25th cycle approximately matches the amplitude in the 24th cycle. It can be expected that the amplitude of the sunspot activity cycle will be close to that of cycle 24.
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REFERENCES
Bumba, V., Do polar faculae terminate or commence an extended cycle of solar activity?, Astron. Inst. Czech. Bull., 1990, vol. 41, pp. 325–332.
Chistyakov, V.F., Metody issledovaniya Solntsa (Solar Research Methods), Vladivostok, 1986.
Li, K.J., Qiu, J., Su, T., et al., Periods of activity cycle of polar faculae, Publ. Astron. Soc. Jpn., 2004, vol. 56, pp. L49–L52.
Li, K.J., Liang, H.F., Gao, P.X., and Su, T.W., High- and low-latitude solar activities: Who leads whom in time phase?, Sol. Phys., 2006, vol. 236, pp. 185–197.
Makarov, V.I., Makarova, V.V., Polar faculae and sunspot cycles, Sol. Phys., 1996, vol. 163, pp. 267–289.
Muñoz-Jaramillo, A., Sheeley, N.R., Zhang, J., et al., Calibrating 100 years of polar faculae measurements: Implications for the evolution of the heliospheric magnetic field, Astrophys. J., 2012, vol. 753, id 146.
Sheeley, N.R., Jr., Polar faculae: 1906–1990, Astrophys. J., 1991, vol. 374, pp. 386–389.
Tanaka, Y., Polar faculae of the Sun (the 4th paper), Publ. Astron. Soc. Jpn., 1964, vol. 16, pp. 336–339.
Tlatov, A.G., The minimum activity epoch as a precursor of the solar activity, Sol. Phys., 2009, vol. 260, pp. 465–477.
Tlatov, A.G., Vasil’eva, V.V., Makarova, V.V., and Otkidychev, P.A., Applying an automatic image-processing method to synoptic observations, Sol. Phys., 2014, vol. 289, pp. 1403–1412.
Weber, H., in Wochenschrift für Astronomie, Meteorologie und Geographie, Halle: Schmidt, 1865a, vol. 8, pp. 38–39; pp. 143–144.
Weber, H., in Wochenschrift für Astronomie, Meteorologie und Geographie, Halle: Schmidt, 1867, vol. 10, pp. 67–70; pp. 155–157.
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The study is supported by the Russian Foundation for Basic Research, project no. 18-02-00098-а.
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Translated by M. Chubarova
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Tlatov, A.G., Tlatova, K.A. Polar and Low-Latitude Faculae in Activity Cycles 23–24. Geomagn. Aeron. 60, 825–830 (2020). https://doi.org/10.1134/S0016793220070245
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DOI: https://doi.org/10.1134/S0016793220070245