Description du projet
Des étoiles super massives aux ondes gravitationnelles
Les ondes gravitationnelles sont des changements invisibles de la courbure de l’espace-temps, à l’image des ondulations à la surface d’un étang, provoquées par certains des événements les plus violents et les plus énergétiques de notre Univers. Elles sont créées par la fusion de deux trous noirs, eux-mêmes engendrés par l’effondrement d’étoiles massives en fin de vie. Avec le soutien du programme Actions Marie Skłodowska-Curie, le projet PROGENITOR établit le profil des étoiles les plus massives et les plus rares que nous connaissions, les étoiles Wolf-Rayet, qui sont à un stade avancé de leur évolution et perdent leur masse à un rythme très élevé. Les études permettront de mieux comprendre l’évolution des étoiles massives et les origines lointaines des ondes gravitationnelles.
Objectif
Stars initially ten times more massive than our Sun play a vital role in the evolution of the Cosmos. Their death is marked by the sudden collapse of their cores into neutron stars or black holes. Somehow, tight couples of massive black holes in the distant Universe occasionally merge, unleashing powerful gravitational waves that are now regularly being measured. The underlying processes that lead to the formation of these pairs remain shrouded in mystery, entailing an intricate story about the life cycle of their PROGENITORs -- the most massive and evolved stars. This reminded the astrophysical community of huge gaps in our knowledge of key processes governing massive-star evolution, related to binary interactions, mass-loss, and mixing. To mitigate this, we must obtain robust empirical constraints on the multiplicity, configuration, and stellar properties of the direct progenitors of black holes in regions that approach the conditions of the distant Universe: the Wolf-Rayet populations of the Magellanic Clouds. The MSCA fellowship offers an ideal platform for achieving this, relying on my unique skills, data, and tools in massive-star spectroscopy with training in state-of-the-art evolution models of stellar populations that I will receive at the University of Amsterdam. I will exploit brand new multi-epoch, multiwavelength monitoring spectroscopy obtained with the Hubble Space Telescope (HST) and Very Large Telescope (VLT). I will establish the physical and orbital properties of entire populations of Wolf-Rayet stars and binaries in the Magellanic Clouds relying on state-off-the-art tools and novel analysis techniques. I will compute population-synthesis models to constrain the evolutionary paths of gravitational-wave mergers. Through this, I will push our understanding of massive stars and gravitational wave sources throughout the Cosmos to new frontiers.
Champ scientifique
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Régime de financement
MSCA-IF - Marie Skłodowska-Curie Individual Fellowships (IF)Coordinateur
1012WX Amsterdam
Pays-Bas