On the possibility of a bimodal solar dynamo

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

A simple way to couple an interface dynamo model to a fast tachocline model is presented, under the assumption that the dynamo saturation is due to a quadratic process and that the effect of finite shear layer thickness on the dynamo wave frequency is analogous to the effect of finite water depth on surface gravity waves. The model contains one free parameter which is fixed by the requirement that a solution should reproduce the helioseismically determined thickness of the tachocline. In this case it is found that, in addition to this solution, another steady solution exists, characterized by a four times thicker tachocline and 4-5 times weaker magnetic fields. It is tempting to relate the existence of this second solution to the occurrence of grand minima in solar activity.

Original languageEnglish
Pages (from-to)777-780
Number of pages4
JournalAstronomische Nachrichten
Volume328
Issue number8
DOIs
Publication statusPublished - Aug 2007

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water depth
shear layers
gravity waves
solar activity
gravity wave
surface wave
occurrences
saturation
magnetic field
requirements
magnetic fields
effect
parameter

Keywords

  • Sun: activity
  • Sun: magnetic fields
  • Sun: rotation

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

On the possibility of a bimodal solar dynamo. / Petrovay, K.

In: Astronomische Nachrichten, Vol. 328, No. 8, 08.2007, p. 777-780.

Research output: Contribution to journalArticle

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