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Register a new userThe CORALIE survey for southern extra-solar planets. XII. Orbital solutions for 16 extra-solar planets discovered with CORALIE
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M. Mayor
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This paper summarizes the information gathered for 16 still unpublished exoplanet candidates discovered with the CORALIE echelle spectrograph mounted on the Euler Swiss telescope at La Silla Observatory. Amongst these new candidates, 10 are typical extrasolar Jupiter-like planets on intermediate- or long-period (100<P<1350d) and fairly eccentric (0.2<e<0.5) orbits (HD19994, HD65216, HD92788, HD111232, HD114386, HD142415, HD147513, HD196050, HD216437, HD216770). Two of these stars are in binary systems. The next 3 candidates are shorter-period planets (HD6434, HD121504) with lower eccentricities among which a hot Jupiter (HD83443). More interesting cases are finally given by the multiple-planet systems HD82943 and HD169830. The former is a resonant P_2/P_1=2/1 system in which planet-planet interactions are influencing the system evolution. The latter is more hierarchically structured.
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The presence of a planet around the K dwarf HD192263 was recently called into question by the detection of a periodic photometric signal with the same period as the one observed in radial velocity. In this paper, we investigate this possibility, using a combination of radial-velocity, photometry, and bisector measurements obtained simultaneously. The results show that while the observed radial-velocity variation is always very stable in phase, period, and amplitude, the photometric signal changes with time. The combined information strongly suggests that the observed radial-velocity variation is being produced by the presence of a planet, as firstly proposed. The photometric variations are either not connected to the planetary companion, or can eventually be induced by the interaction between the planet and the star. Finally, the radial-velocity data further show the presence of a long term trend, whose origin, still not clear, might be related to the presence of another companion to the system.
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