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Related papers: A model of a tidally synchronized solar dynamo

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Guided by the working hypothesis that the Schwabe cycle of solar activity is synchronized by the 11.07 years alignment cycle of the tidally dominant planets Venus, Earth and Jupiter, we reconsider the phase diagrams of sediment accumulation…

Solar and Stellar Astrophysics · Physics 2020-10-07 F. Stefani , J. Beer , A. Giesecke , T. Gloaguen , M. Seilmayer , R. Stepanov , T. Weier

We argue that the most prominent temporal features of the solar dynamo, in particular the Hale cycle, the Suess-de Vries cycle (associated with variations of the Gnevyshev-Ohl rule), Gleissberg-type cycles, and grand minima can be…

Solar and Stellar Astrophysics · Physics 2021-06-23 Frank Stefani , Rodion Stepanov , Tom Weier

Aiming at a consistent planetary synchronization model of both short-term and long-term solar cycles, we start with an analysis of Schove's historical data of cycle maxima. Their deviations (residuals) from the average cycle duration of…

Solar and Stellar Astrophysics · Physics 2020-10-01 F. Stefani , A. Giesecke , M. Seilmayer , R. Stepanov , T. Weier

Solar activity undergoes a variation over time scales of several months known as Rieger-type periodicity, which usually occurs near maxima of sunspot cycles. An early analysis showed that the periodicity appears only in some cycles, and is…

Helioseismology provides important constraints for the solar dynamo problem. However, the basic properties and even the depth of the dynamo process, which operates also in other stars, are unknown. Most of the dynamo models suggest that the…

Solar and Stellar Astrophysics · Physics 2014-02-11 Alexander G. Kosovichev , Valery V. Pipin , Junwei Zhao

The formation of highly magnetized young neutron stars, called magnetars, is still a strongly debated question. A promising scenario invokes the amplification of the magnetic field by the Tayler-Spruit dynamo in a proto-neutron star (PNS)…

High Energy Astrophysical Phenomena · Physics 2025-03-19 Paul Barrère , Jérôme Guilet , Raphaël Raynaud , Alexis Reboul-Salze

In 1969 Leighton developed a quasi-1D mathematical model of the solar dynamo, building upon the phenomenological scenario of Babcock(1961). Here we present a modification and extension of Leighton's model. Using the axisymmetric component…

Solar and Stellar Astrophysics · Physics 2017-03-01 R. H. Cameron , M. Schuessler

Large-scale planetary or stellar magnetic fields generated by a dynamo effect are mostly attributed to flows forced by buoyancy forces in electrically conducting fluid layers. However, these large-scale fields may also be controlled by…

Solar and Stellar Astrophysics · Physics 2015-06-22 David Cébron , Rainer Hollerbach

A new simple dynamo model for stellar activity cycle is proposed. By considering an inhomogeneous mean flow effect on turbulence, it is shown that turbulent cross helicity (velocity--magnetic-field correlation) should enter the expression…

Solar and Stellar Astrophysics · Physics 2016-06-22 Nobumitsu Yokoi , Dieter Schmitt , Valery Pipin , Fujihiro Hamba

In this paper we develop a theory of disturbances induced by the stellar tidal field in a fully convective slowly rotating planet orbiting on a highly eccentric orbit around a central star. We show that there are two contributions to the…

Astrophysics · Physics 2009-11-07 P. B. Ivanov , J. C. B. Papaloizou

We obtain the latitude-time distribution of the averaged tilt angle of solar bipoles. For large bipoles, which are mainly bipolar sunspot groups, the spatially averaged tilt angle is positive in the Northern solar hemisphere and negative in…

Solar and Stellar Astrophysics · Physics 2015-06-15 A. Tlatov , E. Illarionov , D. Sokoloff , V. Pipin

It is proposed that the observed near-surface inflows towards the active regions and sunspot zones provide a nonlinear feedback mechanism that limits the amplitude of a Babcock-Leighton-type solar dynamo and determines the variation of the…

Solar and Stellar Astrophysics · Physics 2015-06-11 R. H. Cameron , M. Schuessler

We examine the effect of dynamical tides raised by a companion on a solar-type star. In these binaries, gravity or g mode oscillations are excited by the companion in the radiative region beneath the convective envelope of the star. They…

Astrophysics · Physics 2007-05-23 C. Terquem , J. C. B. Papaloizou , R. P. Nelson , D. N. C. Lin

We explore the cause of the solar cycle variabilities using a novel 3D Babcock--Leighton dynamo model. In this model, based on the toroidal flux at the base of the convection zone, bipolar magnetic regions (BMRs) are produced with…

Solar and Stellar Astrophysics · Physics 2019-01-30 Bidya Binay Karak , Mark Miesch

The profile of the differential rotation together with the sign of the alpha-effect determine the dynamo wave direction. In early models of the solar dynamo the dynamo wave often leads to a poleward migration of the activity belts. Flux…

Solar and Stellar Astrophysics · Physics 2020-09-30 Detlef Elstner , Yori Fournier , Rainer Arlt

The time series of total solar irradiance (TSI) satellite observations since 1978 provided by ACRIM and PMOD TSI composites are studied. We find empirical evidence for planetary-induced forcing and modulation of solar activity. Power…

Solar and Stellar Astrophysics · Physics 2013-07-31 Nicola Scafetta , Richard C. Willson

Dynamo models relying on the Babcock-Leighton mechanism are successful in reproducing most of the solar magnetic field dynamical characteristics. However, considering that such models operate only above a lower magnetic field threshold,…

Solar and Stellar Astrophysics · Physics 2013-07-17 Sabrina Sanchez , Alexandre Fournier , Katia Pinheiro , Julien Aubert

We revisit the possible turbulent sources of the solar dynamo. Studying axisymmetric mean-field dynamo models, we find that the large-scale poloidal magnetic field could be generated not only by the famous alpha effect, but also by the…

Astrophysics · Physics 2008-12-09 V. V. Pipin , N. Seehafer

It has been suggested that tidal interaction is important for shaping the orbital configurations of close orbiting giant planets. The excitation of propagating waves and normal modes (dynamical tide) will be important for estimating time…

Solar and Stellar Astrophysics · Physics 2023-02-08 J. C. B. Papaloizou , G. J. Savonije

We explore a response of a non-linear non-axisymmetric mean-field solar dynamo model to shallow non-axisymmetric perturbations. After a relaxation period the amplitude of the non-axisymmetric field depends on the initial condition, helicity…

Solar and Stellar Astrophysics · Physics 2015-11-18 V. V. Pipin , A. G. Kosovichev
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