Thesis

From ESPRESSO to Plato: detecting and characterizing Earth-like planets in the presence of stellar noise

• Call:

  IDPASC Portugal - PHD Programme 2014

• Academic Year:

  2014 /2015

• Domain:

  Astrophysics

• Supervisor:

  Nuno Santos

• Co-Supervisor:

• Institution:

  Universidade do Porto

• Host Institution:

  Centro de Astrofísica da Universidade do Porto

• Abstract:

  While the number and variety of discovered extra-solar planets is still an important asset for exoplanet research, the focus of extrasolar planet researchers is now moving towards two main lines: i) the detection of lower and lower mass planets, with the goal of finding an Earth sibling, and ii) the finest characterization of planets orbiting other stars, including their interior structures and atmospheres. Despite the development of a whole new generation of instruments and space missions (like ESOESPRESSO and ESA’s CHEOPS and PLATO missions, on which our team is deeply involved), these goals are not easy to achieve. In particular, the “noise” introduced by stellar magnetic activity has been shown to be a strong source of difficulties for planet search and characterization programs using both high precision radial velocity or photometric transit observations. The present project proposes to investigate the impact and role of stellar activity in precise planet search and characterization projects. For this, we expect the student to develop a numerical tool to simulate the physical effects of stellar magnetic activity (spots, plages, granulation) on precise photometric (transit) and radial velocity measurements. The tool will then be applied to real data (e.g. HARPS and Kepler). The impact of stellar activity on the derivation of precise planet parameters will be investigated in detail. The results of this project have crucial consequences for the full success of instruments like ESPRESSO, CHEOPS, and PLATO.