Narrow frequency-windowed autocorrelations as a diagnostic of solar-like stars

International audienceAims: This paper investigates the diagnostic potential of narrow, frequency-windowed autocorrelation as a tool for probing the properties of solar-like oscillating stars when the determination of individual frequencies is impossible or is subject to large uncertainties, and when mode identification is difficult. Methods: I use theoretical analysis including phase-shifts, modelling, and data analysis. Results: Narrow-windowed autocorrelation of a time series can reveal the variation with frequency of the large separations Delta(nu) and the half large separations Delta01, Delta10, thus helping with mode identification. This technique is applied to the CoRoT p-mode oscillators HD 49933, HD 175726, HD 181420, and HD 181906. Theoretical analysis and modelling are presented to illustrate the technique