Prof. O. Creevey, L. Bigot, T. Guillot, A. Chiavassa
(S2, elective, 3 ECTS)
|Learning Outcomes:||Exoplanets are new windows into our Universe. We want to know what they are made of, how they were formed and ultimately whether they may harbor life. Characterizing exoplanets i.e., measuring their physical parameters and atmospheric properties to infer their structure and com-position is key. They are part of systems including one or several stars and therefore the combined evolution of stars and planets is essential to learn more about these objects. We propose a course that combines expertise on stellar and planetary atmospheres, structure and evolution with the goal to characterize exoplanets and their parent stars.|
|Knowledge and Understanding:||The students will learn the phys-ical principles behind the internal structure, atmosphere and evolution of stars and planets. Both Standard and modern concepts will be presented.|
Theoretical and numerical ap-proaches are proposed : The first part will be dedicated to the derivation of the fundamental equations and the understanding of the general concepts in the fields of stellar physics and planetology. With this background,the students will have the op-portunity to use state-of-the-art numerical codes based on these principles to approach current hot topic problems in exoplane-tology and interpret recent ob-served data.
|Applying Knowledge and Understanding:||Hands-on course: The students will learn how to use the stellar and plane evolution codes CESAM and CEPAM.This will give the the ability to predict physical parameters as a function of in-put mass, composition and age. They will first calculate evolution tracks for the Sun and for Jupiter. They will test how a change in atmospheric boundary condition (e.g., including irradiation for a hot Jupiter) affects the evolution.The students will then perform indi-vidual projects based on recent research in the fields of stellar evolution and exoplanet research.|
|Program||Basics of stellar evolution (O.Creevey, L. Bigot). Classical Stellar Evolution: Main Equations of radiative hydro-static equilibrium, energy trans-port, equations of state (EOS),opacities to understand the HR diagram. Topics on determining planet-host parameters (radius,mass, age). Exploration of the properties with age.Modern developments: Limb Darkening, granulation, stellar cycles, rotation, winds. Conse-quences for the detection and characterization of transiting exoplanets.|
Basics of planet evolution (T.Guillot) Classical Planetary Evolution:Solid & gas planets, importance of EOSs, atmospheric boundary conditions, importance of stellar irradiation. Evolution, heat trans-port, an HR diagram for gaseous planets.Modern developments: Atmo-spheric dynamics, tides, Ohmic dissipation.
Basics of exoplanet atmospheres (A. Chiavassa) Classical Planetary atmospheres: Analytical solution models of planetary atmosphere: radiative hydrostatic equation, concept of radiative equilibrium, Eddington Approximation. Modern developments: green-house effects, stellar contamina-tion. definition of habitability. Re-cap of line transfert, molecular formation. Transmission spec-troscopy. Line detection by cross-correlation techniques.
|Description of how the course is conducted||Powerpoints, lectures, articles, practice of tools and codes|
|Description of the didactic methods||Lectures, exercises and project|
|Description of the evaluation methods||•Written exam on the theoretical lectures (30%), •Oral presentation of homeworks(15%), •Evaluation of the advancement of the project (15%),•Final evaluation during the global oral presentation (40%)|
|Recommended readings||Stellar astrophysics (Leblanc) Lecture notes in stellar evolution (Christiansen-Dalsgaard) Introduction to planetary atmospheres (Sanchez-Lavega)|