Hostname: page-component-745bb68f8f-lrblm Total loading time: 0 Render date: 2025-01-30T23:18:16.170Z Has data issue: false hasContentIssue false
  • English
  • Français

Study of Sun's ‘Hydromagnetic’ Oscillations Using Sunspot Data

Published online by Cambridge University Press:  08 February 2017

M.H. Gokhale ,
J. Javaraiah  and
K.M. Hiremath
M.H. Gokhale
Affiliation:
Indian Institute of Astrophysics Bangalore 560 034 India
J. Javaraiah
Affiliation:
Indian Institute of Astrophysics Bangalore 560 034 India
K.M. Hiremath
Affiliation:
Indian Institute of Astrophysics Bangalore 560 034 India

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Spherical-harmonic-fourier (SHF) analysis of sun's ‘nominal toroidal magnetic field’, computed using sunspot data during 1874-1976, shows that sunspot activity can be considered as possibly originating in interference of sun's axi-symmetric ‘hydromagnetic’ oscillations of odd degrees up to ℓ ≈ 21 and periods ≈ 22y. The relative amplitudes and relative phases of these oscillations remain fairly constant, leading to butterfly diagrams with stable latitude-time correlations on all latitude scales ≳9°. The amplitudes and phases do however undergo slow coherent variations. The main modes (η<11) represent an approximately standing oscillation.

Type
VI. Generation of Solar Magnetic Fields
Information
Symposium - International Astronomical Union , Volume 138: Solar Photosphere: Structure, Convection and Magnetic Fields , 1990 , pp. 375 - 378
Copyright
Copyright © Kluwer 1990 

References

Gokhale, M.H. and Javaraiah, J (1989) ‘Sunspot activity as originating in interference of sun's global MHD oscillations’. paper submitted to MNRAS.Google Scholar
Stenflo, J.O. (1988) ‘Global wave patterns in the sun's magnetic field’, Astrophys & Sp. Sci., 144, 321.CrossRefGoogle Scholar