All Figures

$\begin{figure} \par\includegraphics[width=8.5cm]{6369f1a.ps}\par\includegraphics[width=8.5cm]{6369f1b.ps}\end{figure}$ Figure 1: Upper panel: cumulative histograms of $\vert r_i/\sigma _i\vert$ for SARG data. The diamonds show the observed data, and the solid curve shows the result expected for a Gaussian-distributed noise. Lower panel: ratio of the observed to the expected histograms, indicating the fraction of "good'' data points.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8.5cm]{6369f2.ps}\end{figure}$ Figure 2: The power spectrum of the weighted data. A power excess around $1~\rm mHz$ is evident. The inset shows the power spectrum of the window function for a sine-wave signal of amplitude $1~\rm m~s^{-1}$ , sampled in the same way as the observations. The power units are the same as those of the main figure.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8.5cm]{6369f3.ps}\end{figure}$ Figure 3: The first-order spacing calculated over several frequency ranges, as determined from the comb-response analysis. The line shows the mean value of $55.7~\rm\mu Hz$ , with a standard error of $\pm 1.4~\rm\mu Hz$ .
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8.5cm]{6369f4.ps}\end{figure}$ Figure 4: The cumulative comb-response obtained as the sum of the individual comb-responses for each central frequency $\nu _{0}$ . The peak is centered at $\Delta\nu = 56\pm 1~\rm\mu Hz$ . The error is the FWHM of the peak.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8.5cm]{6369f5.ps}\end{figure}$ Figure 5: The echelle diagram as derived from the "standard'' extraction of frequencies.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8.5cm]{6369f6.ps}\end{figure}$ Figure 6: The echelle diagram as derived from the "modified'' extraction of frequencies.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8.5cm]{6369f7.ps}\end{figure}$ Figure 7: The mean power folded at the large-separation frequency as a function of frequency modulo of $55.90~\rm\mu Hz$ . The positions of the modes with l=0,1,2 are indicated, together with the positions of the daily side-bands.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8.5cm]{6369f8.ps}\end{figure}$ Figure 8: Velocity amplitude per mode (l=0,1) as a function of frequency. The horizontal line at $0.45~\rm m~s^{-1}$ represents the mean amplitude of the p-mode peak power in the frequency interval $0.6{-}1.4~\rm mHz$ . The scale of intensity is also given, together with the positions of l=0 modes, as derived from asymptotic relationship (1).
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8.8cm]{6369f9.ps}\end{figure}$ Figure 9: The rms scatter of the 10 identified frequencies as a function of mode lifetime obtained by several thousand simulations. The intersection of the horizontal line of the observed scatter with the solid curve obtained by simulations indicates that the mode lifetime is $1.97^{+0.43}_{-0.35}~\rm d$ . The horizontal line of coherent oscillation scatter, corresponding to an infinite mode lifetime, is also indicated. The frequency spread reflects essentially the width of the Lorentzian profile.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8.8cm]{6369f10.ps}\end{figure}$ Figure 10: The amplitude of the 6 largest amplitude detected modes, for l=0,1,2 as a function of the mode lifetime. The bars indicate the $1\sigma$ error.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8.8cm]{6369f11a.ps}\par\includegraphics[width=8.8cm]{6369f11b.ps}\end{figure}$ Figure 11: Simulated Procyon p-mode power spectrum obtained by using the De Ridder et al. (2006) simulator, not including noise and rotational splittings. The length of the time-series is $10~\rm d$ and the mode lifetime is $2~\rm d$ .
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8.8cm]{6369f12a.ps}\par\includegraphics[width=8.8cm]{6369f12b.ps}\end{figure}$ Figure 12: The same simulation as in Fig. 11, but for a mode lifetime of $0.5~\rm d$ . Note that the frequency spreads are larger and peak amplitudes smaller than those of the modes seen in Fig. 11.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8.8cm]{6369f13.ps}\end{figure}$ Figure 13: Time series of EW measurements as derived from the combination of all the lines reported in Table 3.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8.8cm]{6369f14.ps}\end{figure}$ Figure 14: The weighted power spectrum $\rm {\it EW}_{\rm best}-\langle\rm {\it EW}_{\rm best}\rangle$ derived from the combination of the measurements of all the lines of Table 3. There is no power excess in the range $0.5{-}1.5~\rm mHz$ , but the background power in the range $0.2 {-} 0.7~\rm mHz$ could be a signature of stellar granulation.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8.8cm]{6369f15.ps}\end{figure}$ Figure 15: Smoothed power density spectra (PDS) of Procyon granulation noise as obtained from SARG (dashed line, this project) and AAT/ESO EW 1999, squares, (Kjeldsen et al. 1999) spectroscopy, and MOST (Matthews et al. 2004) and WIRE (Bruntt et al. 2005) space photometry (continuous lines). The PDS derived from the PS of Fig. 14 is shown in the background. Power density is expressed in $\rm ppm^2~\mu Hz^{-1}$ .
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8.5cm]{6369f1a.ps}\par\includegraphics[width=8.5cm]{6369f1b.ps}\end{figure}$	Figure 1: Upper panel: cumulative histograms of $\vert r_i/\sigma _i\vert$ for SARG data. The diamonds show the observed data, and the solid curve shows the result expected for a Gaussian-distributed noise. Lower panel: ratio of the observed to the expected histograms, indicating the fraction of "good'' data points.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=8.5cm]{6369f2.ps}\end{figure}$	Figure 2: The power spectrum of the weighted data. A power excess around $1~\rm mHz$ is evident. The inset shows the power spectrum of the window function for a sine-wave signal of amplitude $1~\rm m~s^{-1}$ , sampled in the same way as the observations. The power units are the same as those of the main figure.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=8.5cm]{6369f3.ps}\end{figure}$	Figure 3: The first-order spacing calculated over several frequency ranges, as determined from the comb-response analysis. The line shows the mean value of $55.7~\rm\mu Hz$ , with a standard error of $\pm 1.4~\rm\mu Hz$ .
Open with DEXTER

$\begin{figure} \par\includegraphics[width=8.5cm]{6369f4.ps}\end{figure}$	Figure 4: The cumulative comb-response obtained as the sum of the individual comb-responses for each central frequency $\nu _{0}$ . The peak is centered at $\Delta\nu = 56\pm 1~\rm\mu Hz$ . The error is the FWHM of the peak.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=8.5cm]{6369f5.ps}\end{figure}$	Figure 5: The echelle diagram as derived from the "standard'' extraction of frequencies.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=8.5cm]{6369f6.ps}\end{figure}$	Figure 6: The echelle diagram as derived from the "modified'' extraction of frequencies.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=8.5cm]{6369f7.ps}\end{figure}$	Figure 7: The mean power folded at the large-separation frequency as a function of frequency modulo of $55.90~\rm\mu Hz$ . The positions of the modes with l=0,1,2 are indicated, together with the positions of the daily side-bands.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=8.5cm]{6369f8.ps}\end{figure}$	Figure 8: Velocity amplitude per mode (l=0,1) as a function of frequency. The horizontal line at $0.45~\rm m~s^{-1}$ represents the mean amplitude of the p-mode peak power in the frequency interval $0.6{-}1.4~\rm mHz$ . The scale of intensity is also given, together with the positions of l=0 modes, as derived from asymptotic relationship (1).
Open with DEXTER

$\begin{figure} \par\includegraphics[width=8.8cm]{6369f10.ps}\end{figure}$	Figure 10: The amplitude of the 6 largest amplitude detected modes, for l=0,1,2 as a function of the mode lifetime. The bars indicate the $1\sigma$ error.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=8.8cm]{6369f11a.ps}\par\includegraphics[width=8.8cm]{6369f11b.ps}\end{figure}$	Figure 11: Simulated Procyon p-mode power spectrum obtained by using the De Ridder et al. (2006) simulator, not including noise and rotational splittings. The length of the time-series is $10~\rm d$ and the mode lifetime is $2~\rm d$ .
Open with DEXTER

$\begin{figure} \par\includegraphics[width=8.8cm]{6369f12a.ps}\par\includegraphics[width=8.8cm]{6369f12b.ps}\end{figure}$	Figure 12: The same simulation as in Fig. 11, but for a mode lifetime of $0.5~\rm d$ . Note that the frequency spreads are larger and peak amplitudes smaller than those of the modes seen in Fig. 11.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=8.8cm]{6369f13.ps}\end{figure}$	Figure 13: Time series of EW measurements as derived from the combination of all the lines reported in Table 3.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=8.8cm]{6369f14.ps}\end{figure}$	Figure 14: The weighted power spectrum $\rm {\it EW}_{\rm best}-\langle\rm {\it EW}_{\rm best}\rangle$ derived from the combination of the measurements of all the lines of Table 3. There is no power excess in the range $0.5{-}1.5~\rm mHz$ , but the background power in the range $0.2 {-} 0.7~\rm mHz$ could be a signature of stellar granulation.
Open with DEXTER