The GAPS Programme with HARPS-N@TNG: A Search for Additional Planets in Transiting Planet Systems

We present results from the Global Architecture of Planetary Systems (GAPS) Long-Term Programme with the HARPS-N spectrograph on the TNG. We focus on the GAPS program element encompassing a targeted search for additional, outer planets in a sample of known transiting Hot Jupiter systems. We describe the status of the program, and present preliminary findings, including: 1) significant refinement of the orbits of some transiting planets; 2) evidence for previously undetected long-period objects 3) a study of the mass-period-eccentricity relation for transiting systems in connection with tidal dissipation effects; 4) a homogeneous determination of stellar parameters (metallicity, effective temperature, surface gravity) in transiting systems to assess the significance of emerging differences among samples uncovered by different transit surveys, and 5) a study of the Ca H&K activity levels of transiting planet hosts in connection with the presence of the close-in orbiting companion.