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Relationship between group sunspot number and Wolf sunspot number [PDF]
Astronomische Nachrichten, 2010 Continuous wavelet transform and cross-wavelet transform have been used to investigate the phase periodicity and synchrony of the monthly mean Wolf ($R_{z}$) and group ($R_{g}$) sunspot numbers during the period of June 1795 to December 1995. The Schwabe
Echer +20 more
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Forecasting the number of sunspots for solar cycle 25 utilizing the facebook prophet model [PDF]
Scientific ReportsThe solar cycle, also referred to as the solar magnetic activity cycle, represents a nearly periodic change in solar activity occurring approximately every 11 years, as evidenced by the observation of sunspot numbers.
H. I. Abdel Rahman, W. A. Badawy
doaj +2 more sources
The new Sunspot Number: assembling all corrections [PDF]
Solar Physics, 2015 The Sunspot Number, created by R.Wolf in 1849, provides a direct long-term record of solar activity from 1700 to the present. In spite of its central role in multiple studies of the solar dynamo and of the past Sun-Earth relations, it was never submitted
Clette, Frédéric, Lefèvre, Laure
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Hemispheric sunspot numbers 1874–2020 [PDF]
Astronomy & Astrophysics, 2021 Context. Previous studies show significant north–south asymmetries for various features and indicators of solar activity. These findings suggest some decoupling between the two hemispheres over the solar cycle evolution, which is in agreement with dynamo theories.
Astrid M. Veronig +4 more
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Journal of Space Weather and Space Climate, 2023 On a centennial timescale, solar activity oscillates quasi-periodically and also tends to occasionally get into a low-activity period. The Dalton Minimum (circa 1790s–1820s) was one of such low-activity periods that had been captured in telescopic ...
Hayakawa Hisashi +3 more
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Fractal Dimension and Maximum Sunspot Number in Solar Cycle [PDF]
Journal of Astronomy and Space Sciences, 2006 The fractal dimension is a quantitative parameter describing the characteristics of irregular time series. In this study, we use this parameter to analyze the irregular aspects of solar activity and to predict the maximum sunspot number in the following ...
R.-S. Kim +4 more
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Tests of Sunspot Number Sequences: 4. Discontinuities Around 1946 in Various Sunspot Number and Sunspot-Group-Number Reconstructions [PDF]
Solar Physics, 2016 In press with Solar ...
Lockwood, M., Owens, M. J., Barnard, L.
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A Unified Shape Model For Sunspot Number Cycles
Ratio Mathematica, 2021 Modelling and prediction of sunspot number time series is an unavoidable activity in the space object re-entry prediction community. Different mathematical functions have been proposed in the literature as sunspot number cycle model, since the McNish ...
GP Beena, A Sabarinath, AK Anilkumar
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Sunspot observations at Kawaguchi Science Museum: 1972 – 2013
Geoscience Data Journal, 2023 Individual sunspot observations have formed a ground basis of international sunspot number, a unique reference for long‐term solar variability in the centennial timescale.
Hisashi Hayakawa +5 more
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ANALYSIS OF SUNSPOT NUMBER FLUCTUATIONS [PDF]
Fractals, 2004 Monthly averages of the sunspot number visible on the sun, observed from 1749, Zurich Observatory, and from 1848 other observatories, have been analyzed. This time signal presents a frequency power spectra with a clear 1/fα behavior with α≃0.8±0.2.
Fanchiotti, H. +3 more
openaire +2 more sources