France, KevinKevinFranceArulanantham, NicoleNicoleArulananthamFossati, LucaLucaFossatiLANZA, Antonino FrancescoAntonino FrancescoLANZA0000-0001-5928-7251Linsky, Jeffrey L.Jeffrey L.LinskyRedfield, SethSethRedfieldLoyd, RobertRobertLoydSchneider, ChristianChristianSchneider2020-10-052020-10-052018http://hdl.handle.net/20.500.12386/27569Exoplanet magnetic fields have proven notoriously hard to detect, despite theoretical predictions of substantial magnetic field strengths on close-in extrasolar giant planets. It has been suggested that stellar and planetary magnetic field interactions can manifest as enhanced stellar activity relative to nominal age-rotation-activity relationships for main sequence stars or enhanced activity on stars hosting short-period massive planets. In a recent study of M and K dwarf exoplanet host stars, we demonstrated a significant correlation between the relative luminosity in high-temperature stellar emission lines (L(ion)/L_Bol) and the “star-planet interaction strength”, M_plan/a_plan. Here, we expand on that work with a survey of G, K, and M dwarf exoplanet host stars obtained in two recent far-ultraviolet spectroscopic programs with the Hubble Space Telescope. We have measured the relative luminosities of stellar lines C II, Si III, Si IV, and N V (formation temperatures from 30,000 - 150,000 K) in a sample of ~60 exoplanet host stars and an additional ~40 dwarf stars without known planets. We present results on star-planet interaction signals as a function of spectral type and line formation temperature, as well as a statistical comparison of stars with and without planets.ELETTRONICOenConference abstracthttp://live-aas-web.pantheonsite.io/sites/default/files/2019-10/aas_231_abstracts.pdf2018AAS...23134906FFIS/05 - ASTRONOMIA E ASTROFISICAERC sectors::Physical Sciences and Engineering::PE9 Universe sciences: astro-physics/chemistry/biology; solar systems; stellar, galactic and extragalactic astronomy, planetary systems, cosmology, space science, instrumentation::PE9_2 Planetary systems sciences