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Related papers: Solar activity forecast with a dynamo model

200 papers

We present a 3D kinematic solar dynamo model in which poloidal field is generated by the emergence and dispersal of tilted sunspot pairs (more generally Bipolar Magnetic Regions, or BMRs). The axisymmetric component of this model functions…

Solar and Stellar Astrophysics · Physics 2015-06-18 Mark S. Miesch , Mausumi Dikpati

Context. Solar activity cycles vary in amplitude and duration. The variations can be at least partly explained by fluctuations in dynamo parameters. Aims. We want to restrict uncertainty in fluctuating dynamo parameters and find out which…

Solar and Stellar Astrophysics · Physics 2018-07-18 L. L. Kitchatinov , A. V. Mordvinov , A. A. Nepomnyashchikh

One prominent feature of solar cycle is its irregular variation in its cycle strength, making it challenging to predict the amplitude of the next cycle. Studies show that fluctuations and nonlinearity in generating poloidal field throughout…

Solar and Stellar Astrophysics · Physics 2025-11-10 Bidisha Dey , Anu Sreedevi , Bidya Binay Karak

It is well accepted that the solar cycle originates from a magnetohydrodynamics dynamo deep inside the Sun. Many dynamo models have long been proposed based on a lot of observational constraints. In this paper, using 342 NSO/Kitt Peak solar…

Astrophysics · Physics 2009-06-23 W. B. Song

A combination of diamagnetic pumping and a nonlocal alpha-effect of the Babcock-Leighton type in a solar dynamo model helps to reproduce observations of solar magnetic activity. The period of the solar cycle can be reproduced without…

Solar and Stellar Astrophysics · Physics 2015-05-30 L. L. Kitchatinov , S. V. Olemskoy

The prediction of the strength of an upcoming solar cycle has been a long-standing challenge in the field of solar physics. The inherent stochastic nature of the underlying solar dynamo makes the strength of the solar cycle vary in a wide…

Solar and Stellar Astrophysics · Physics 2023-10-03 Akash Biswas , Bidya Binay Karak , Pawan Kumar

The level of solar magnetic activity, as exemplified by the number of sunspots and by energetic events in the corona, varies on a wide range of time scales. Most prominent is the 11-year solar cycle, which is significantly modulated on…

Solar and Stellar Astrophysics · Physics 2017-07-26 Robert Cameron , Manfred Schüssler

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

A solar-type dynamo model in a spherical shell is developed with allowance for random dependence of the poloidal field generation mechanism on time and latitude. The model shows repeatable epochs of strongly decreased amplitude of magnetic…

Solar and Stellar Astrophysics · Physics 2015-06-17 S. V. Olemskoy , L. L. Kitchatinov

A model for the solar dynamo, consistent in global flow and numerical method employed with the differential rotation model, is developed. The magnetic turbulent diffusivity is expressed in terms of the entropy gradient, which is controlled…

Solar and Stellar Astrophysics · Physics 2017-06-28 L. L. Kitchatinov , A. A. Nepomnyashchikh

Magnetohydrodynamic interactions between plasma flows and magnetic fields is fundamental to the origin and sustenance of the 11-year sunspot cycle. These processes are intrinsically three-dimensional (3D) in nature. Our goal is to construct…

Solar and Stellar Astrophysics · Physics 2019-03-06 R. Kumar , L. Jouve , D. Nandy

The prediction of the strength of future solar cycles is of interest because of its practical significance for space weather and as a test of our theoretical understanding of the solar cycle. The Babcock-Leighton mechanism allows…

Solar and Stellar Astrophysics · Physics 2018-08-29 Jie Jiang , Jing-Xiu Wang , Qi-Rong Jiao , Jin-Bin Cao

The large-scale magnetic field observed at the solar surface is produced by the interior dynamo process. Whether this surface field also provides the dominant seed for the subsequent dynamo cycle, however, remains controversial, with…

Solar and Stellar Astrophysics · Physics 2026-04-16 Binghang Li , Jie Jiang , Yukun Luo

Reliable prediction of the solar cycle is a formidable challenge, yet it is increasingly vital in our technology-dependent society as solar activity drives space weather. Various methods, including precursors, nonlinear curve fitting and…

Solar and Stellar Astrophysics · Physics 2026-04-20 Bidya Binay Karak

The solar dynamo is essentially a cyclic process in which the toroidal component of the magnetic field is converted into the poloidal one and vice versa. This cyclic loop is disturbed by some nonlinear and stochastic processes mainly…

Solar and Stellar Astrophysics · Physics 2024-03-12 Aparup Ghosh , Pawan Kumar , Amrita Prasad , Bidya Binay Karak

The most widely accepted model of the solar cycle is the flux transport dynamo model. This model evolved out of the traditional $\alpha \Omega$ dynamo model which was first developed at a time when the existence of the Sun's meridional…

Solar and Stellar Astrophysics · Physics 2023-07-26 Gopal Hazra , Dibyendu Nandy , Leonid Kitchatinov , Arnab Rai Choudhuri

Observations of the solar magnetic cycle showed that the amplitude of the cycle did not grow all the time in the past. Thus, there must be a mechanism to halt the growth of the magnetic field in the Sun. We demonstrate a recently proposed…

Solar and Stellar Astrophysics · Physics 2021-02-02 Bidya Binay Karak

The hemispheric asymmetry of sunspot activity observed possesses a regular component varying on a time scale of several solar cycles whose origin and properties are currently debated. This paper addresses the question of whether the…

Solar and Stellar Astrophysics · Physics 2019-05-08 Alexander Nepomnyashchikh , Sudip Mandal , Dipankar Banerjee , Leonid Kitchatinov

According to the scheme of action of the solar dynamo, the poloidal magnetic field can be considered a source of production of the toroidal magnetic field by the solar differential rotation. From the polar magnetic field proxies, it is…

Solar and Stellar Astrophysics · Physics 2021-09-13 V. N. Obridko , D. D. Sokoloff , V. V. Pipin , A. S. Shibalova , I. M. Livshits

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