The 2021 MERAC Prize for the Best Early Career Researcher in Theoretical Astrophysics is awarded to Dr Antoine Strugarek (CEA Saclay, France) for ground- breaking contributions in stellar astrophysics, including dynamo theory, predictions of solar flares and pioneering work on star-exoplanet interactions. The prize from the MERAC foundation (Mobilization for European Research in Astrophysics and Cosmology) is awarded each year by the European Society of Astronomy (ESA).
A 3D model of the Sun
Antoine Strugarek tackled the difficult problem of the magnetic confinement of turbulent plasmas using ambitious MHD and giro-kinetic simulations. He produced, with Professor Jean-Paul Zahn, the first global MHD model of the Sun in 3D, from the deep radiative zone to the surface. He is a highly recognized expert on several topics: turbulent plasma confinement and turbulent dynamos, evolution of magnetism in star-planet systems, prediction and evolution of solar flares. His main results include an innovative method to control turbulence by acting on the temperature gradient, improving the stability of Tokamak plasmas, magnetically confined plasmas for the production of energy by nuclear fusion.
In the case of the Sun, he was also able to show that magnetic fields cannot prevent the propagation of the solar tachocline unlike horizontal turbulence.
Antoine Strugarek led an unprecedented study on stellar dynamos. He conducted for the first time a coherent suite of convective dynamo simulations, spanning several effective temperatures and Rossby numbers, to measure the influence of rotation and stellar mass on the generation of the magnetic field. This allowed him to derive scale laws for stellar magnetism, which are now the reference in the community. He also worked on a solar flare forecasting model, based on self-organizing critical models.
3D model of the sun showing the internal and external magnetic field. Copyright DAp / CEA.
The Solar Orbiter mission
After a stay in Canada, Antoine Strugarek has been a researcher since 2018 in the Laboratory Dynamic of Stars, (Exo) planets and their Environment (LDE3) of the Department of Astrophysics of the CEA headed by Allan Sacha Brun, where he developed leading simulations of stellar winds and star-planet magnetic interactions. LDE3 is a member of the WHOLESUN project funded by the European Research Council (ERC) whose objective is to determine over the next six years how the magnetic field is generated inside the Sun and how it creates solar spots on its surface and flares in its highly stratified atmosphere. Antoine Strugarek's work is essential in particular to prepare for the operation of the Solar Orbiter mission of the European Space Agency (ESA), a probe launched in February 2020 which will begin its observations of the Sun starting Novembre 2021.
The Solar Orbiter mission by A. Strugarek
See: The MERAC Prize press release (2 March 2021)
See also: - First detection of the X-ray spectro-imager (STIX) of a Solar flare and first images of Solar Orbiter (July 16, 2020)
- The WHOLESUN project: understanding the physical mechanisms behind the eruptive activity of the Sun and its stellar twins (October 23, 2018)
- The origin of the solar cycle unveiled (Jul 13, 2017)
Content : J.M. Bonnet-Bidaud - European Astronomical Society
• Structure and evolution of the Universe › Planets, star's formation and dynamics, interstellar medium
• Department of Astrophysics (DAp) // UMR AIM
