ARE THE SHAPES OF THE P-MODE PEAKS 'DISTORTED' BY THE SOLAR CYCLE WHEN THEY ARE OBSERVED IN LONG, MULTI-YEAR POWER FREQUENCY SPECTRA?

摘要

We seek to address whether the solar activity cycle 'distorts' the underlying shapes of low-l p-mode peaks when the peaks are observed in power spectra made from data spanning large fractions of the cycle period. We present analytical descriptions of the expected profiles, and validate the predictions through the use of artificial seismic timeseries data, in which temporal variations of the oscillator parameters are introduced. Our main finding is that for the Sun-like shifts the distortion of the Lorentzian-like profiles is very small. Preliminary analysis suggest that if the mode peaks are fitted with the usual Lorentzian-like models, then bias from the distortion is expected to be at a level that is comparable to, or smaller than, the parameter uncertainties expected for multi-year datasets.