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The predictability, or lack thereof, of the solar cycle is governed by numerous separate physical processes that act in unison in the interior of the Sun. Magnetic flux transport and the finite time delay it introduces, specifically in the…

Astrophysics · Physics 2009-11-13 A. R. Yeates , D. Nandy , D. H. Mackay

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

Extreme solar activity fluctuations and the occurrence of solar grand minima and maxima episodes, are well established, observed features of the solar cycle. Nevertheless, such extreme activity fluctuations and the dynamics of the solar…

Solar and Stellar Astrophysics · Physics 2018-03-30 D. Passos , D. Nandy , S. Hazra , I. Lopes

Fluctuations in the Sun's magnetic activity, including episodes of grand minima such as the Maunder minimum have important consequences for space and planetary environments. However, the underlying dynamics of such extreme fluctuations…

Solar and Stellar Astrophysics · Physics 2014-06-12 Soumitra Hazra , Dário Passos , Dibyendu Nandy

Recent results indicate that the Babcock-Leighton mechanism for poloidal field creation plays an important role in the solar cycle. However, modelling this mechanism has not always correctly captured the underlying physics. In particular,…

Solar and Stellar Astrophysics · Physics 2014-04-08 Soumitra Hazra , Dibyendu Nandy

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

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

We present the first global, three-dimensional simulations of solar/stellar convection that take into account the influence of magnetic flux emergence by means of the Babcock-Leighton (BL) mechanism. We have shown that the inclusion of a BL…

Solar and Stellar Astrophysics · Physics 2015-06-03 Mark S. Miesch , Benjamin P. Brown

Having advanced knowledge of solar activity is important because the Sun's magnetic output governs space weather and impacts technologies reliant on space. However, the irregular nature of the solar cycle makes solar activity predictions a…

Solar and Stellar Astrophysics · Physics 2013-12-31 Dibyendu Nandy , Bidya Binay Karak

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

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

Prediction of the Sun's magnetic activity is important because of its effect on space environment and climate. However, recent efforts to predict the amplitude of the solar cycle have resulted in diverging forecasts with no consensus.…

Solar and Stellar Astrophysics · Physics 2012-12-07 Bidya Binay Karak , Dibyendu Nandy

Although systematic measurements of the solar polar magnetic field exist only from mid 1970s, other proxies can be used to infer the polar field at earlier times. The observational data indicate a strong correlation between the polar field…

Astrophysics · Physics 2009-11-13 Jie Jiang , Piyali Chatterjee , Arnab Rai Choudhuri

Parameters of a special kind of \alpha-effect known in dynamo theory as the Babcock-Leighton mechanism are estimated using the data of sunspot catalogs. The estimates evidence the presence of the Babcock-Leighton \alpha-effect on the Sun.…

Solar and Stellar Astrophysics · Physics 2013-05-14 S. V. Olemskoy , A. R. Choudhuri , L. L. Kitchatinov

The solar cycle is generated by a magnetohydrodynamic dynamo mechanism which involves the induction and recycling of the toroidal and poloidal components of the Sun's magnetic field. Recent observations indicate that the Babcock-Leighton…

Solar and Stellar Astrophysics · Physics 2025-05-22 Shaonwita Pal , Dibyendu Nandy

At present, Babcock-Leighton flux transport solar dynamo models appear as the most promising model for explaining diverse observational aspects of the sunspot cycle. The success of these flux transport dynamo models is largely dependent…

Solar and Stellar Astrophysics · Physics 2016-11-15 Soumitra Hazra , Dibyendu Nandy

The Sun is a magnetic star whose cyclic activity is thought to be linked to internal dynamo mechanisms. A combination of numerical modelling with various levels of complexity is an efficient and accurate tool to investigate such intricate…

Solar and Stellar Astrophysics · Physics 2015-05-19 L. Jouve , M. R. E. Proctor , G. Lesur

Aims: We aim to investigate how converging flows towards active regions affect the surface transport of magnetic flux, as well as their impact on the generation of the Sun's poloidal field. The inflows constitute a potential non-linear…

Solar and Stellar Astrophysics · Physics 2016-12-21 David Martin-Belda , Robert H. Cameron

The flux transport dynamo, in which the poloidal magnetic field is generated by the Babcock--Leighton mechanism and the meridional circulation plays a crucial role, has emerged as an attractive model for the solar cycle. Based on…

Solar and Stellar Astrophysics · Physics 2018-09-05 Arnab Rai Choudhuri

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
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