All Figures

$\begin{figure} \par\includegraphics[width=7.9cm,clip]{4084fig1.eps}\end{figure}$ Figure 1: Distribution of planet to primary-star mass ratios for the known exoplanets and low-mass brown dwarfs. The HARPS detections are represented by the hatched histogram. Planet symbols indicate the positions of Jupiter-, Neptune-, and Uranus-mass objects.
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In the text

$\begin{figure} \par\includegraphics[angle=270,width=8.25cm,clip]{4084fig2.eps}\end{figure}$ Figure 2: Ca II H ( $\lambda$ = 3968.47 Å) absorption line region of the summed HARPS spectra for HD 4308. Re-emission in the core of the line is absent, showing the low chromospheric activity of the star.
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In the text

$\begin{figure} \par\includegraphics[width=7.9cm,clip]{4084fig3.eps}\end{figure}$ Figure 3: Bisector velocity span as a function of the measured radial velocity. No correlation is found supporting a non-intrinsic origin for the radial-velocity variation.
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In the text

$\begin{figure} \par\includegraphics[width=8cm,clip]{4084fig4.eps}\end{figure}$ Figure 4: Histogram of the observed radial-velocity dispersion ( $\sigma _{RV}$ ) of the stars in the HARPS "high-precision'' sub-programme. It has been produced using the data obtained with the new observing strategy and includes only stars with more than 3 measurements. The position of the planets detected with HARPS is indicated by the hatched area.
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In the text

$\begin{figure} \par\includegraphics[width=8cm,clip]{4084fig5.eps}\end{figure}$ Figure 5: Intermediate season of HARPS radial velocities for HD 4308. The best Keplerian fit to the data (solid curve) gives a minimum mass of 14.1 $M_{\oplus }$ and an orbital period of 15.56 days for the planet.
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In the text

$\begin{figure} \par\includegraphics[width=8.15cm,clip]{4084fig6.eps}\end{figure}$ Figure 6: Phase-folded radial velocities of HD 4308 superimposed on the best Keplerian orbital solution (solid curve). The 3 older points obtained before introducing the new observing strategy (see text) are indicated by open symbols.
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In the text

$\begin{figure} \par\includegraphics[width=8.05cm,clip]{4084fig7.eps}\end{figure}$ Figure 7: Metallicity distribution of the sample of extrasolar planet hosts for planets with shorter periods than 20 days. Stars with Neptune-mass planets are indicated by the shaded histogram.
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In the text

$\begin{figure} \par\includegraphics[width=7.9cm,clip]{4084fig1.eps}\end{figure}$	Figure 1: Distribution of planet to primary-star mass ratios for the known exoplanets and low-mass brown dwarfs. The HARPS detections are represented by the hatched histogram. Planet symbols indicate the positions of Jupiter-, Neptune-, and Uranus-mass objects.
Open with DEXTER

$\begin{figure} \par\includegraphics[angle=270,width=8.25cm,clip]{4084fig2.eps}\end{figure}$	Figure 2: Ca II H ( $\lambda$ = 3968.47 Å) absorption line region of the summed HARPS spectra for HD 4308. Re-emission in the core of the line is absent, showing the low chromospheric activity of the star.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=7.9cm,clip]{4084fig3.eps}\end{figure}$	Figure 3: Bisector velocity span as a function of the measured radial velocity. No correlation is found supporting a non-intrinsic origin for the radial-velocity variation.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=8cm,clip]{4084fig4.eps}\end{figure}$	Figure 4: Histogram of the observed radial-velocity dispersion ( $\sigma _{RV}$ ) of the stars in the HARPS "high-precision'' sub-programme. It has been produced using the data obtained with the new observing strategy and includes only stars with more than 3 measurements. The position of the planets detected with HARPS is indicated by the hatched area.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=8cm,clip]{4084fig5.eps}\end{figure}$	Figure 5: Intermediate season of HARPS radial velocities for HD 4308. The best Keplerian fit to the data (solid curve) gives a minimum mass of 14.1 $M_{\oplus }$ and an orbital period of 15.56 days for the planet.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=8.15cm,clip]{4084fig6.eps}\end{figure}$	Figure 6: Phase-folded radial velocities of HD 4308 superimposed on the best Keplerian orbital solution (solid curve). The 3 older points obtained before introducing the new observing strategy (see text) are indicated by open symbols.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=8.05cm,clip]{4084fig7.eps}\end{figure}$	Figure 7: Metallicity distribution of the sample of extrasolar planet hosts for planets with shorter periods than 20 days. Stars with Neptune-mass planets are indicated by the shaded histogram.
Open with DEXTER