Rafael García
Stay at the IAC: 28/05/18 to 24/06/18
Research line: Stellar Physics and Exoplanets
Dr. Rafael A. García is director of research at the Astrophysics division (DAp) of the Atomic Energy Commission (CEA) in Saclay, France.
He obtained his PhD for the “Universidad de La Laguna (Tenerife, Spain)” in 1996. After a two-years post-doc at the CEA and a short stay at the NSO in Tucson (AZ, USA), he obtained a permanent position as an astronomer at the DAp/CEA-Saclay in France in September 1998. In 2012, he obtained the degree of “Habilitation à diriger des recherches” at the Paris-Diderot University and in 2013 he became Director of Research at the CEA. Since 2014 he is responsible for the Stellar physics section at the “Laboratoire of Excellence (LABEX) Physics of the two infinites and its Origines (P2IO)” at the University of Paris-Saclay created in 2012 in the south of Paris regrouping a total of 17 institutions (including 3 Universities, several engineering schools, national research institutions and research laboratories).
His research is devoted to study the structure and evolution of solar-like pulsating stars from main sequence to red giants using seismic techniques to probe solar and stellar interiors. In particular, he is interested in solar and stellar dynamics including internal angular momentum evolution and stellar magnetic cycles. He combines observational and data analysis work with the development of new space instrumentation. He is the institutional PI at the CEA of the GOLF instrument onboard SoHO and the ESA M3 PLATO mission in which he is also responsible for 3 scientific working packages.
Scientific activity during the period visiting the IAC:
During his stay at the IAC, he will work within the “Sismología solar y estelar y búsqueda de exo-planetas” group. He will work with: Dr. Savita Mathur on the improvements of the asteroseismic A2Z pipeline to refine the detection of global seismic parameters and the understanding of the non detection of modes in the solar-like main-sequence stars observed by the Kepler mission; with Dr. Antonio Jiménez on the characterization of the acoustic modes of about 50 main-sequence solar-like pulsating stars observed during the first four campaigns of the K2 mission; with Dr. Fernando Pérez-Hernández on the impact of magnetic activity cycle in the determination of global stellar parameters such as mass, radius and age; with Dr. Clara Régulo on the differences in the seismic properties of the acoustic modes when standard “Maximum-likelihood” fitting methods are compared to “Bayesian” techniques. Finally, he will work with Dr. Pere L. Pallé on the analysis of Arcturus observed with SONG. Further discussions are expected with the exoplanet group, in particular with Dr. Roi Alonso about the preparation of the exoplanet light curves for PLATO and with Dr. Hannu Parviainen about the use of Gaussian processes in astroseismology and the determination of surface rotation in stars.
Complementing this stay, his two PhD students are spending 3 weeks each to work at the IAC funded by the Paris-Diderot University. The second-year Phd student Mansour Benbakoura is working with Dr. Paul Beck and Dr. Fernando Pérez Hernández on the characterization and modeling of 20 binary systems in which the primary is a red giant star observed by Kepler. The first-year Phd student Lisa Bugnet is working with her co-phd supervisor Dr. Savita Mathur on the extraction of surface gravities of low-mass stars observed by Kepler using a new methodology involving machine learning technics.
