English
Related papers

Related papers: Solar Dynamo Model with Diamagnetic Pumping and No…

200 papers

The Sun's magnetic dynamo cycle features a distinct pattern: a propagating region of sunspot emergence appears around 30 degrees latitude and vanishes near the equator every 11 years. Moreover, longitudinal flows called "torsional…

Solar dynamo models require some mechanism for magnetic field concentration near the base of the convection zone in order to generate super-kilogauss toroidal fields with sufficiently large (~10^{24} Mx) magnetic flux. We consider the…

Solar and Stellar Astrophysics · Physics 2016-09-21 L. Kitchatinov , A. Nepomnyashchikh

The sunspot cycle is the magnetic cycle of the Sun produced by the dynamo process. A central idea of the solar dynamo is that the toroidal and the poloidal magnetic fields of the Sun sustain each other. We discuss the relevant observational…

Solar and Stellar Astrophysics · Physics 2023-01-02 Arnab Rai Choudhuri

The paper presents a study of kinematic axisymmetric mean-field dynamo models for a case of the meridional circulation with a deep-seated stagnation point and a strong return flow at the bottom of the convection zone. This kind of…

Solar and Stellar Astrophysics · Physics 2015-05-27 V. V. Pipin , A. G. Kosovichev

We studied the effect of the perturbation of the meridional flow in the activity belts detected by local helioseismology on the development and strength of the surface magnetic field at the polar caps. We carried out simulations of…

Solar and Stellar Astrophysics · Physics 2015-05-19 J. Jiang , E. Isik , R. H. Cameron , D. Schmitt , M. Schuessler

Observations of the sun suggest that solar activities systematically create north-south hemispheric asymmetries. For instance, the hemisphere in which the sunspot activity is more active tends to switch after the early half of each solar…

Solar and Stellar Astrophysics · Physics 2017-04-12 D. Syukuya , K. Kusano

Physical models aimed to reproduce basic features of the solar sunspot cycle are typically based on the solar dynamo mechanism. Usually qualitative arguments are used to define parameters of the model, among which a challenging component is…

Solar and Stellar Astrophysics · Physics 2026-03-12 E. Illarionov , R. Stepanov , K. M. Kuzanyan , V. Kisielius

Global and semi-global convective dynamo simulations of solar-like stars are known to show a transition from an anti-solar (fast poles, slow equator) to solar-like (fast equator, slow poles) differential rotation (DR) for increasing…

Solar and Stellar Astrophysics · Physics 2019-11-25 M. Viviani , M. J. Käpylä , J. Warnecke , P. J. Käpylä , M. Rheinhardt

A physically consistent model of magnetic field generation by convection in a rotating spherical shell with a minimum of parameters is applied to the Sun. Despite its unrealistic features the model exhibits a number of properties resembling…

Solar and Stellar Astrophysics · Physics 2015-06-04 R. D. Simitev , F. H. Busse

We point out the difficulties in carrying out direct numerical simulation of the solar dynamo problem and argue that kinematic mean-field models are our best theoretical tools at present for explaining various aspects of the solar cycle in…

Solar and Stellar Astrophysics · Physics 2015-06-05 Arnab Rai Choudhuri

Stellar magnetic fields are produced by a magnetohydrodynamic dynamo mechanism working in their interior -- which relies on the interaction between plasma flows and magnetic fields. The Sun, being a well-observed star, offers an unique…

Solar and Stellar Astrophysics · Physics 2015-06-03 Dibyendu Nandy

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

Observations show that faster-rotating stars tend to have stronger magnetic activity and shorter magnetic cycles. The cyclical magnetic activity of the Sun and stars is believed to be driven by the dynamo process. The success of the…

Solar and Stellar Astrophysics · Physics 2024-06-05 Zebin Zhang , Jie Jiang , Leonid Kitchatinov

The change of sound speed has been found at the base of the convection during the solar cycles, which can be used to constrain the solar internal magnetic field. We aim to check whether the magnetic field generated by the solar dynamo can…

Solar and Stellar Astrophysics · Physics 2021-06-02 Shaolan Bi , Tanda Li , Kang Liu , Jie Jiang , Yaguang Li , Jinghua Zhang , Xianfei Zhang , Yaqian Wu

Observations in polarized emission reveal the existence of large-scale coherent magnetic fields in a wide range of spiral galaxies. Radio-polarization data show that these fields are strongly inclined towards the radial direction, with…

Astrophysics · Physics 2009-11-13 Oliver Gressel , Udo Ziegler , Detlef Elstner , Günther Rüdiger

Simple models of magnetic field generation by convection in rotating spherical shells exhibit properties resembling those observed on the sun. The {assumption of the Boussinesq approximation made in these models} prevents a realistic…

Solar and Stellar Astrophysics · Physics 2015-06-03 Radostin D. Simitev , Friedrich H. Busse

The dynamic activity of stars such as the Sun influences (exo)planetary space environments through modulation of stellar radiation, plasma wind, particle and magnetic fluxes. Energetic stellar phenomena such as flares and coronal mass…

Solar and Stellar Astrophysics · Physics 2023-07-26 Prantika Bhowmik , Jie Jiang , Lisa Upton , Alexandre Lemerle , Dibyendu Nandy

Context: Large-scale magnetic fields resulting from hydromagnetic dynamo action may differ substantially in their time dependence. Cyclic field variations, characteristic for the solar magnetic field, are often explained by an important…

Solar and Stellar Astrophysics · Physics 2015-05-27 M. Schrinner , L. Petitdemange , E. Dormy

The operation of the solar global dynamo appears to involve many dynamical elements. Self-consistent MHD simulations which realistically incorporate all of these processes are not yet computationally feasible, though some elements can now…

Astrophysics · Physics 2008-11-26 Allan Sacha Brun , Mark S. Miesch , Juri Toomre

An explanation is suggested for the north-south asymmetry of the polar magnetic field reversal in the current cycle of solar activity. The contribution of the Babcock-Leighton mechanism to the poloidal field generation is estimated using…

Solar and Stellar Astrophysics · Physics 2015-07-15 L. L. Kitchatinov , A. I. Khlystova