Abstract
The presence of a planet around the K dwarf HD 192263 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.
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.