Sunspot number series envelope and phase
Abstract
The 1700topresent sunspot number series R(t) is presently noted to be representable by an expression involving the angular frequency corresponding to a 22year period, the instantaneous envelope amplitude, the instantaneous phase of a complex and timevarying analytic function, an undulation of low amplitude and period lasting for about 30 of the 22year cycles, and a nonlinear operator whose primary effect is the introduction of a small amount of third harmonic with a period of about 7 years. The third harmonic is an expected consequence of minor nonlinearity in the dependence of the arbitrarily defined sunspot number series on the physical cause of sunspots. A complex envelope is discerned whose intrinsic behavior may be studied to reveal statistics bearing on the origin of the solar cycle. The results imply a deep monochromatic oscillator whose influence is propagated to the observable surface via a timevarying medium.
 Publication:

Australian Journal of Physics
 Pub Date:
 1985
 DOI:
 10.1071/PH851009
 Bibcode:
 1985AuJPh..38.1009B
 Keywords:

 Solar Magnetic Field;
 Sunspot Cycle;
 Computational Astrophysics;
 Hilbert Transformation;
 Magnetic Field Inversions;
 Magnetic Flux;
 Stellar Envelopes;
 Stellar Oscillations;
 Time Series Analysis;
 Solar Physics