Dr Louis Amard
Postdoctoral Research Fellow
My main research interest is understanding the angular momentum evolution of young low-mass stars, from the arrival on the birthline to the end of the main sequence and beyond, as well as understanding how this evolution affect the environment of the star. When the star arrives on the main sequence, less than 1% of its initial AM content is still present, and during the main sequence, the star's angular momentum is decreased by an other factor ten to a hundred.
What I am currently doing :
To answer those questions, I'm mostly using the STAREVOL evolution code that include a way to account for internal redistribution of angular momentum in the star, completed by a boundary condition that can account for a surface angular momentum loss due to either magnetized wind and/or star-disc interaction. In the frame of the AWESoMeStars project, I will develop modules for the open source evolutionary code MESA, that will allows to account for the most up-to-date prescriptions for angular momentum losses during both star-disc interaction and main sequence evolution.
Past work :
I did a Master thesis with C. Charbonnel in Geneva working on angular momentum transport by Internal gravity waves during the pre-main sequence of solar-type stars where I discovered the use of the evolutionary code STAREVOL.
Then, during my PhD, under the supervision of A. Palacios (University of Montpellier, FR) and C. Charbonnel (University of Geneva, CH), I used again STAREVOL to test the different existing prescriptions for internal as well as external AM transport/extraction. Parallely I've been developping new ways to redistribute the AM in stellar radiative regions with S. Mathis and V. Prat (CEA Paris, FR). These works on a stellar evolution code lead me to compute various grids of models for different topics with different teams from giant planet detection and characterisation to stellar magnetic field estimation via tidal star-planet interaction and habitable zone estimation around solar-type stars.
Those can be found here.