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Related papers: Deciphering Solar Magnetic Activity. The Solar Cyc…

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Analysis of over 36 years of time series data from the NSO/AFRL/Sac Peak K-line monitoring program elucidates five components of the variation of the seven measured chromospheric parameters: (a) the solar cycle (period ~ 11 years), (b)…

Solar and Stellar Astrophysics · Physics 2015-06-15 Jeffrey Scargle , Stephen Keil , Pete Worden

One of the most striking manifestations of orderly behavior emerging out of complex interactions in any astrophysical system is the 11-year cycle of sunspots. However, direct sunspot observations and reconstructions of long-term solar…

Solar and Stellar Astrophysics · Physics 2025-04-24 Chitradeep Saha , Suprabha Mukhopadhyay , Dibyendu Nandy

Helioseismology has provided very detailed inferences about rotation of the solar interior. Within the convection zone the rotation rate roughly shares the latitudinal variation seen in the surface differential rotation. The transition to…

Astrophysics · Physics 2009-11-11 J. Christensen-Dalsgaard

Recent work has revealed an phenomenological picture of the how the $\sim$11-year sunspot cycle of Sun arises. The production and destruction of sunspots is a consequence of the latitudinal-temporal overlap and interaction of the toroidal…

Solar and Stellar Astrophysics · Physics 2015-06-23 Scott W. McIntosh , Robert J. Leamon

A new formula for predicting solar cycles based on the current theoretical understanding of the solar cycle from flux transport dynamo is presented. Two important processes---fluctuations in the Babcock-Leighton mechanism and variations in…

Solar and Stellar Astrophysics · Physics 2019-08-07 Gopal Hazra , Arnab Rai Choudhuri

The differential rotation plays a crucial role in the dynamics of the Sun. We study the solar rotation and its correlation with solar activity by applying a modified machine learning algorithm to identify and track coronal bright points…

Solar and Stellar Astrophysics · Physics 2024-07-30 Zahra Shokri , Nasibe Alipour , Hossein Safari

Solar activity has a cyclic nature with the ~11-year Schwabe cycle dominating its variability on the interannual timescale. However, solar cycles are significantly modulated in length, shape and magnitude, from near-spotless grand minima to…

Solar and Stellar Astrophysics · Physics 2023-03-29 Akash Biswas , Bidya Karak , Ilya Usoskin , Eckhard Weisshaar

The total solar irradiance (TSI) varies on timescales of minute to centuries. On short timescales it varies due to the superposition of intensity fluctuations produced by turbulent convection and acoustic oscillations. On longer scale…

Solar and Stellar Astrophysics · Physics 2022-10-12 V. Penza , F. Berrilli , L. Bertello , M. Cantoresi , S. Criscuoli , P. Giobbi

The solar-activity-cycle minimum observed between Cycles 23 and 24 is generally regarded as being unusually deep and long. That minimum is being followed by one of the smallest amplitude cycles in recent history. We perform an in-depth…

Solar and Stellar Astrophysics · Physics 2017-04-19 A. -M. Broomhall

In this work we introduce a new way of binning sunspot group data with the purpose of better understanding the impact of the solar cycle on sunspot properties and how this defined the characteristics of the extended minimum of cycle 23. Our…

Recently, Rozelot & Eren pointed out that the first solar gravitational moment (J2) might exhibit a temporal variation. The suggested explanation is through the temporal variation of the solar rotation with latitude. This issue is deeper…

Solar and Stellar Astrophysics · Physics 2023-01-19 Saliha Eren , Jean-Pierre Rozelot

A detailed investigation of the magnetic properties of young Sun-like stars can provide valuable information on our Sun's magnetic past and its impact on the early Earth. We determine the properties of the moderately rotating young Sun-like…

We assess the global-scale dynamo action achieved in a simulation of a sun-like star rotating at three times the solar rate. The 3-D MHD Anelastic Spherical Harmonic code, using slope-limited diffusion, is employed to capture convection and…

Solar and Stellar Astrophysics · Physics 2013-11-01 Kyle Augustson , Allan Sacha Brun , Mark Steven Miesch , Juri Toomre

Research results from solar-dynamo models show the northern and southern hemispheres may evolve separately throughout the solar cycle. The observed phase lag between the hemispheres provides information regarding the strength of hemispheric…

Solar and Stellar Astrophysics · Physics 2015-05-18 A. A. Norton , J. C. Gallagher

Based on data obtained from Wilcox Solar Observatiry the solar polar magnetic fields reversals in cycles 21\,--\,25 were considered. The results indicate that the polarity reversal occurs at the maximum of sunspot activity of each cycle,…

Solar and Stellar Astrophysics · Physics 2025-11-03 Irina A. Bilenko

In 1965 Paul D. Jose published his discovery that both the motion of the Sun about the center of mass of the solar system and periods comprised of eight Hale magnetic sunspot cycles with a mean period of ~22.37 years have a matching…

Solar and Stellar Astrophysics · Physics 2017-01-19 Gerald E. Pease , Gregory S. Glenn

Convection, differential rotation, and meridional circulation of solar plasma are studied based on helioseismic data covering the period from May 2010 to August 2024, significantly prolonged compared to that previously considered. Depth…

Solar and Stellar Astrophysics · Physics 2025-04-22 A. V. Getling , A. G. Kosovichev

Whether the upcoming cycle 24 of solar activity will be strong or not is being hotly debated. The solar cycle is produced by a complex dynamo mechanism. We model the last few solar cycles by `feeding' observational data of the Sun's polar…

Astrophysics · Physics 2008-11-26 Arnab Rai Choudhuri , Piyali Chatterjee , Jie Jiang

Although there are now some tentative signs that the start of cycle 24 has begun there is still considerable interest in the somewhat unusual behaviour of the current solar minimum and the apparent delay in the true start of the next cycle.…

Solar and Stellar Astrophysics · Physics 2010-03-23 Stephen Fletcher , Roger New , Anne-Marie Broomhall , William Chaplin , Yvonne Elsworth

The flux of energetic particles originating from the Sun fluctuates during the solar cycles. It depends on the number and properties of Active Regions (ARs) present in a single day and associated solar activities, such as solar flares and…