Based on observations collected at the La Silla Observatory, ESO (Chile), with the CORALIE spectrograph at the 1.2-m Euler Swiss telescope and at the La Palma Observatory, Spain, with the P7 photometer at the 1.2-m MERCATOR Belgian telescope.

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See e.g. http://obswww.unige.ch/Exoplanets

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... presented

The radial-velocity and photometry measurements are available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/406/373

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...Henry et al. (2002)

A value compatible with the measured activity level of the star, that implyes a $P_{{\rm rot}}\sim21$ days (Noyes et al. 1984); however, and as we will see in Sect. 4.4, it is not completely clear if the 24.5-day photometric period is really related with the rotation period of the star.

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... width

values of 0.25 and 4.30 km s^-1 are respectively chosen as typical values for CORALIE spectra.

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... visible

Although not the case with the CORALIE spectra (R=50 000), we should add that the spectral resolution might also impose limits to the validity of the bisector test. In fact, given that the broadening factors essentially sum up in quadrature, it is very difficult to put in evidence intrinsic line asymmetries when the instrumental profile is significantly broader than the intrinsic line profile.

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... 0.004 mag

Besides this photometric campaign, C. Nitschelm (private communication) has furnished us a series of photometric measurements of HD 192263 obtained during the last three years at the Danish 0.5-m telescope (La Silla, ESO, Chile). The data show no special photometric variations for this star over the whole period. However, given the obtained precision of only about 0.01 mag, these observations cannot be used to strongly constrain our results, and in particular to check for the presence of short period photometric variations.

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... left

The quality of the data does not permit to precisely access the phase of this periodic signal.

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... stable

We have tried to verify if there was any relation between the radial-velocity residuals and the BIS. Nothing is seen, maybe because of the large errors in the individual measurements, when compared to the magnitude of the effect.

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... phenomena

In this context, note also that for K dwarfs the convective velocities are not very high (smaller than for F dwarfs), reducing the probability of radial-velocity variations induced by convective inhomogeneities (Santos et al. 2000b; Saar & Donahue 1997; Saar et al. 1998).

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... earth

It should be noted, however, that the timescales of the tidal motions in the low-density stellar atmosphere are short (Cuntz et al. 2000).

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