Low frequency signal in the GOLF measurements

This paper shows the results obtained using a revisited method to normalize the velocity evaluation extracted from the measurements, for roughly 14 years of GOLF data. For the search of g modes, we calculate the low frequency power spectrum of the signal with 2 different approaches: • The classical calculation of the power spectrum of the velocity signal. • An alternative calculation, extracting first the variations along the time of the p-mode frequencies, then calculating the power spectrum of those frequency modulation [4]. Both spectra are compared to the g-mode frequency spectrum calculated for a solar model. Several observed frequencies are in close agreement with the calculated g modes. A careful statistical analysis of this result should now follow.