All Figures

$\begin{figure} \par\includegraphics[width=8cm]{1953fig1.eps}\end{figure}$ Figure 1: Location of the convection simulations in the HR diagram. The symbol sizes vary proportionally to the stellar radii. Evolutionary tracks of stars, with masses as indicated, were calculated on the base of Christensen-Dalsgaard's stellar evolutionary code(Christensen-Dalsgaard 1982; Christensen-Dalsgaard & Frandsen 1983a).
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In the text

$\begin{figure} \par\includegraphics[width=8cm]{1953fig2.eps}\par\includegraphics[width=8cm]{1953fig3.eps}\par\includegraphics[width=8cm]{1953fig4.eps}\end{figure}$ Figure 2: The filled dots represent $\chi _{ k}$ obtained from the 3D simulations for the wavenumber k at which E(k) is maximum and at the layer where the excitation is maximum in the simulation. The results are presented for three simulations: Procyon ( top), the Sun ( middle) and $\alpha$ Cen B ( bottom). The solid curves represent the Lorentzian form, Eq. (5), the dashed curves the Gaussian form Eq. (4), and the dot dashed curves the exponential form Eq. (6).
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In the text

$\begin{figure} \par\includegraphics[width=8cm]{1953fig5.eps}\par\includegraphics[width=8cm]{1953fig6.eps}\par\includegraphics[width=8cm]{1953fig7.eps}\end{figure}$ Figure 3: Same as Fig. 2 for $k=10~ k_{\rm min}$ where $k_{\min}$ is the first non-zero wavenumber of the simulation.
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In the text

$\begin{figure} \par\includegraphics[width=15cm]{1953fig8.eps}\end{figure}$ Figure 4: Excitation rates, ${\cal P}$ , are presented as functions of mode frequency for six of the seven convection simulations listed in Tables 1 and 2. Each triangle corresponds to a single evaluation of the 3D work integral estimated for a given eigenfrequency according to Eq. (1). The dot-dashed lines correspond to a running mean of the triangle symbols performed over five frequencies. The solid and dashed lines correspond to the excitation rates calculated with the semi-analytical method and using the Gaussian and the exponential forms of $\chi _{ k}$ , respectively. All results shown are obtained as the sum of contributions from the two sources of excitation: excitation by the turbulent pressure and excitation by the non-adiabatic gas pressure.
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In the text

$\begin{figure} \par\includegraphics[width=9cm]{1953fig9.eps}\par\includegraphics[width=9cm]{1953fig10.eps}\end{figure}$ Figure 5: Top: as in Fig. 4 for solar simulations only. The solid line corresponds to the semi-analytical calculations based on a Lorentzian $\chi _{ k}$ and a simulation with a spatial resolution of $253\times 253 \times 82$ . The other lines are running means over five frequencies of the direct calculation based on solar simulations with different spatial resolution: $253\times 253 \times 82$ (dashed line), $125 \times 125 \times 82$ (dot dashed line) and $50\times 50 \times 82$ (dot dot dashed line). Bottom: the solid and dashed lines have the same meaning as in the top figure. The dot-dashed line corresponds to the semi-analytical calculations based on a Gaussian $\chi _{ k}$ .
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In the text

$\begin{figure} \resizebox{9cm}{!}{\includegraphics{1953fig11.eps}} \end{figure}$ Figure 6: ${\cal P}_{\rm max}$ versus L/M where L is the luminosity and M is the mass of the 1D models associated with the 3D simulations. The triangles correspond to the direct calculations (labeled as "DirEx 3D'' in the legend), and the other symbols correspond to the semi-analytical calculations using the three forms of $\chi _{ k}$ : the crosses assume a Gaussian, the diamonds an exponential and the squares a Lorentzian, respectively. Each set of ${\cal P}_{\rm max}$ is fitted by a power law of the form (L/M)^s where s is the slope of the power law. The line-styles correspond to the three semi-analytical cases and the direct calculations, as indicated in the lower right corner of the plot.
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In the text

$\begin{figure} \resizebox{9cm}{!}{\includegraphics{1953fig12.eps}} \end{figure}$ Figure 7: Same as Fig. 6 for $V_{\rm max}/V_{{\rm max},\odot }$ , the maximum of the mode amplitudes relative to the observed solar value ( $V_{{\max},\odot}=33.1~\pm 0.9$ cm s^-1). The filled symbols correspond to the stars for which solar-like oscillations have been detected in Doppler velocity. The lines - except the dashed line - correspond to the power laws obtained from the predicted scaling laws for ${\cal P}_{\rm max}$ (Fig. 6) and estimated values of the damping rates $\eta _{\rm max}$ (see text for details). Results for two different eddy time-correlation functions, $\chi _{ k}$ , are presented: Lorentzian (solid line) and Gaussian (dot-dashed line) functions. For comparison the dashed line shows the result by HG02. Values of the slope sv are given on the plot and in Table 3.
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In the text

$\begin{figure} \par\includegraphics[width=8cm]{1953fig1.eps}\end{figure}$	Figure 1: Location of the convection simulations in the HR diagram. The symbol sizes vary proportionally to the stellar radii. Evolutionary tracks of stars, with masses as indicated, were calculated on the base of Christensen-Dalsgaard's stellar evolutionary code(Christensen-Dalsgaard 1982; Christensen-Dalsgaard & Frandsen 1983a).
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$\begin{figure} \par\includegraphics[width=8cm]{1953fig5.eps}\par\includegraphics[width=8cm]{1953fig6.eps}\par\includegraphics[width=8cm]{1953fig7.eps}\end{figure}$	Figure 3: Same as Fig. 2 for $k=10~ k_{\rm min}$ where $k_{\min}$ is the first non-zero wavenumber of the simulation.
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