Low-order stellar dynamo models

Antonia Lindsay Wilmot-Smith, P C H Martens, D Nandy, E R Priest, S M Tobias

Research output: Contribution to journalArticlepeer-review

23 Citations (Scopus)

Abstract

Stellar magnetic activity - which has been observed in a diverse set of stars including the Sun originates via a magnetohydrodynamic dynamo mechanism working in stellar interiors. The full set of magnetohydrodynamic equations governing stellar dynamos is highly complex, and so direct numerical simulation is currently out of reach computationally. An understanding of the bifurcation structure, likely to be found in the partial differential equations governing such dynamos, is vital if we are to understand the activity of solar-like stars and its evolution with varying stellar parameters such as rotation rate. Low-order models are an important aid to this understanding, and can be derived either as approximations of the governing equations themselves or by using bifurcation theory to obtain systems with the desired structure. We use normal-form theory to derive a third-order model with robust behaviour. The model is able to reproduce many of the basic types of behaviour found in observations of solar-type stars. In the appropriate parameter regime, a chaotic modulation of the basic cycle is present, together with varying periods of low activity such as that observed during the solar Maunder minima.

Original languageEnglish
Pages (from-to)1167-1172
Number of pages6
JournalMonthly Notices of the Royal Astronomical Society
Volume363
DOIs
Publication statusPublished - 11 Nov 2005

Keywords

  • Sun : activity
  • Sun : rotation
  • stars : activity
  • stars : late-type
  • stars : rotation
  • MAIN-SEQUENCE STARS
  • SOLAR DYNAMO
  • MAGNETIC ACTIVITY
  • MAUNDER MINIMUM
  • NONLINEAR DYNAMOS
  • SADDLE-NODE
  • CYCLE
  • INTERMITTENCY
  • ALPHA
  • SUN

Fingerprint

Dive into the research topics of 'Low-order stellar dynamo models'. Together they form a unique fingerprint.

Cite this