A S T R O P H Y S I Q U E S T E L L A I R E T H E O R I Q U E E T A S T E R O S I S M O L O G I E S TA R W O R K S H O P U L g H a u t e s - f a g n e s S t a t i o n S e p t e m b e r 1 5 2 0 1 7 Melanie Godart
o Modelisation of oscillations o Development of methods to
probe the stellar interior Internal structure and
evolution of stars Modelisation
o Mass
o Input physics (metallicity, opacity tables, …
o Convection, transport processes
à age, radius, evolutionary state,…
o Modelisation of oscillations o Development of methods to
probe the stellar interior Internal structure and
evolution of stars Modelisation
o Mass
o Input physics (metallicity, opacity tables, …
o Convection, transport processes
à age, radius, evolutionary state,…
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M A S S I V E O B S TA R S β C E P H & S P B 𝛄 D O R S U N & S O L A R - L I K E S TA R S sdBGAPHE Massive stars ARC ORCA
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ASTA 5Star modelling for characterising the planet host stars
CSL
Cheops, Nanesse
GAPHE Massive stars ARC ORCA CSL Cheops, Nanesse
Star modelling for characterising the planet host stars
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University of Birmingham Geneva Observatory Observatoire de Paris IAC ASTA 7 Montpellier Los Alamos Université de Montreal ToulouseSc
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ASTA Improved stellar modelsCHEOPS
PLATO
GAIA
SPECULOOS
For the Galaxy
(2013-…) For exoplanets Stellar characterization (mass, radius, age, habitability) (ongoing) (launch 2018) (launch 2026)
KEPLER
(2008- 2017)Sc
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ASTA Improved stellar modelsPLATO
(launch 2026)Planetary Transits and Oscillations of stars
v find and study a large number of extrasolar planetary systems
v emphasis on the properties of terrestrial planets in the habitable zone around solar-like stars
v investigate seismic activity in stars, enabling the precise characterisation of the planet-host star, including its age.
RECENT ACTIVITIES
Massive stars Low mass models --The Sun -- NanosatelliteAccurate stellar modelling is essential for accurate planet modelling
11 7.2 Gyr 10.0 Gyr 11.0 Gyr 13.7 Gyr 1.0 Gyr 4.1 Gyr log Te ff(K) lo g (L ∗ /L ⊙ ) 3.705 3.71 3.715 3.72 −0. 5 −0. 45 −0. 4 M∗= 0.73M⊙, Fe/H=−0.26, Yarb M∗= 0.77M⊙, Fe/H=−0.23, YG M∗= 0.81M⊙, Fe/H=−0.20, Y⊙
Exemple: the star HD97658 and its super Earth (Van Grootel, Gillon et al. 2014)
Star: mass and radius known to 5-10%
Planet: mass and radius known to 5-10% Planet composition:
60-99% rocks, 1-40% ice
LOW-MASS STARS
PLANET-HOST STAR CHARACTERISATION
THE SUN
NANESSE
Nano-satelite for Asteroseismology of the NEarest Stellar System with Exoplanets
⚭ Observing 𝝰Cen in order to improve the detection of the modes via photometry ⚭ Check for planet transits
⚭ 6 months observations
NANESSE
Nanosatellite for Asteroseismology of the NEarest Stellar System with Exoplanets
⚭ Observing 𝝰Cen for improving the detection of the modes via photometry
⚭ Check for planet transits ⚭ 6 month observations
