All Figures

$\begin{figure} \par\includegraphics[height=14.6cm,width=5.3cm,angle=90,clip]{8833f1.ps}\end{figure}$ Figure 1: The Total Solar Irradiance time series (level 2.0 data of the VIRGO experiment) used to simulate Sun-like microvariability in the present investigation. Small horizontal red dashes at the bottom of the plot mark gaps in the time series.
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In the text

$\begin{figure} \par\includegraphics[height=9.6cm,width=7.4cm,clip]{8833f2.ps}\end{figure}$ Figure 2: Distributions of the residuals of the TSI best fit along solar cycle 23 obtained with the 3-spot model (solid black histograms) and the 200-harmonic fitting (dashed green histograms) for the three labelled time intervals corresponding to the minimum ( top panel), intermediate ( middle panel) and maximum ( bottom panel) of activity. Solid-black lines and green-dashed lines are Gaussian best fits to the 3-spot and the 200-harmonic residual distributions, respectively. The standard deviations of the Gaussian best fits are indicated in the panels with $\sigma _{\rm 3s}$ and $\sigma _{\rm h}$ , referring to the 3-spot model and the 200-harmonic fitting, respectively.
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In the text

$\begin{figure} \par\includegraphics[height=13cm,width=6.6cm,angle=90,clip]{8833f3.ps}\end{figure}$ Figure 3: Power spectra of the residuals of the TSI best fit obtained with the 3-spot model ( left panel) and the 200-harmonic fitting ( right panel). Different linestyles and colors indicate different levels of activity: black-solid line: maximum; green-dashed line: intermediate; and, red-dotted line: minimum.
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In the text

$\begin{figure} \par\includegraphics[height=7.6cm,width=9.2cm,angle=90,clip]{8833f4.ps}\end{figure}$ Figure 4: Distributions of the values of $\alpha$ as defined by Eq. (2) obtained by analysing light curves with transits of a planet of $1.5~R_{\oplus}$ . Each set is characterized by a different orbital period of the planet (as labelled). The standard deviation of the white Gaussian noise is in all cases 200 ppm. The red and blue vertical dot-dashed lines indicate the 1 percent threshold for the 200-harmonic fitting and the 3-spot model, respectively. Red-solid histograms show the statistics of light curves where the period was correctly identified after applying the 200-harmonic method, blue-solid histograms show those after applying the 3-spot method, respectively. Dashed histograms refer to the statistics of light curves where the period was incorrectly identified, with the same color coding.
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In the text

$\begin{figure} \par\includegraphics[height=5.2cm,width=5cm,angle=90,clip]{8833f5.ps}\end{figure}$ Figure 5: Residuals obtained with the 200-harmonic method (red-dotted line) and the 3-spot method (blue-dashed line) for a noiseless light curve containing only transits; the black-solid line is the light variation during the transit. Note the Gibbs phenomenon affecting the residuals obtained with the 200-harmonic fit and the smaller distortion of the transit profile obtained with the 3-spot method.
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In the text

$\begin{figure} \par\includegraphics[height=4.9cm,width=5cm,angle=90,clip]{8833f6.ps}\end{figure}$ Figure 6: Signal-to-noise ratio $\alpha _{\rm h}$ obtained with the 200-harmonic fitting versus the corresponding value $\alpha _{\rm 3s}$ obtained with the 3-spot model for light curves with $R = 1.5~R_{\oplus}$ , $P \leq 25$ d and standard deviation of the noise of 200 ppm. The dot-dashed red and blue lines indicate the $\alpha$ thresholds for the 200-harmonic fitting and the 3-spot model, respectively. The yellow region of the plot indicates transits detected with the 3-spot model that go undetected with the 200-harmonic fitting.
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In the text

$\begin{figure} \par\includegraphics[height=14.6cm,width=5.3cm,angle=90,clip]{8833f1.ps}\end{figure}$	Figure 1: The Total Solar Irradiance time series (level 2.0 data of the VIRGO experiment) used to simulate Sun-like microvariability in the present investigation. Small horizontal red dashes at the bottom of the plot mark gaps in the time series.
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$\begin{figure} \par\includegraphics[height=13cm,width=6.6cm,angle=90,clip]{8833f3.ps}\end{figure}$	Figure 3: Power spectra of the residuals of the TSI best fit obtained with the 3-spot model ( left panel) and the 200-harmonic fitting ( right panel). Different linestyles and colors indicate different levels of activity: black-solid line: maximum; green-dashed line: intermediate; and, red-dotted line: minimum.
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