English

The irregularities of the sunspot cycle and their theoretical modelling

Solar and Stellar Astrophysics 2015-06-18 v1

Abstract

The 11-year sunspot cycle has many irregularities, the most promi- nent amongst them being the grand minima when sunspots may not be seen for several cycles. After summarizing the relevant observational data about the irregularities, we introduce the flux transport dynamo model, the currently most successful theoretical model for explaining the 11-year sunspot cycle. Then we analyze the respective roles of nonlinearities and random fluctuations in creating the irregularities. We also discuss how it has recently been realized that the fluctuations in meridional circula- tion also can be a source of irregularities. We end by pointing out that fluctuations in the poloidal field generation and fluctuations in meridional circulation together can explain the occurrences of grand minima.

Keywords

Cite

@article{arxiv.1312.3408,
  title  = {The irregularities of the sunspot cycle and their theoretical modelling},
  author = {Arnab Rai Choudhuri},
  journal= {arXiv preprint arXiv:1312.3408},
  year   = {2015}
}

Comments

Invited paper for the C.V. Raman 125th birth anniversary issue of Indian Journal of Physics