Stellar and planet formation history across the disk and halo of the Milky Way
for a starting date of 2021 and fully funded (4 years) by a prestigious European Research Council Consolidator Grant
(UK and EU applicants are welcome)
The stellar population near the Sun, which contains the brightest specimens of almost all types of stars and planets, is a key research area that remains poorly explored. The spacecraft Gaia has provided, for the first time, a near complete census of all stars within 100 pc of the Sun, including 400,000 stars and 20,000 white dwarfs, with on average at least one planet per star. However, a full understanding of the local stellar and planet population is still a major challenge, despite fundamental advances made by my research group on stellar evolution and exotic stellar mergers. Modelling the combined astrometric, photometric and spectroscopic data, your PhD project will unlock the enormous potential of this local stellar sample in tracing the stellar formation history for the disk, halo and associated clusters of the Milky Way. The assembly of galaxies like our own is itself paramount to understand the evolution of the low redshift Universe. You will also make use of evolved planetary systems, where rocky planet debris are currently being accreted in the convection zone of their white dwarf hosts, to provide an unique window into the beginning and evolution of rocky planet formation in our Galaxy. The project will be at the forefront of the stellar revolution triggered by Gaia and both computational and data science (interpreting observations) sub-projects are possible depending on your interests.
- You will start the project by mining through a sample of 50,000 wide binaries identified from Gaia, where both stars were born at the same but have never interacted, to assess the accuracy of modelled stellar ages for both main-sequence stars and white dwarfs.
- The project will then extend to the full 100 pc stellar sample, where you will model spectroscopic follow-up data for stars and white dwarfs through my exclusive membership of the 4MOST survey, a gold mine for exotic planet and stellar discoveries.
- (Option A - Data mining) Using both photometric and spectroscopic stellar parameters, you will deliver a precise stellar formation history for the disk and halo of our Milky Way. You will use white dwarfs that are currently accreting rocky material into their convection zones to trace rocky planet formation for the last 13.8 Gyr and for stellar hosts of all masses.
- (Option B - Computational) You will lead the improvement of stellar evolution and interior physics models to obtain precise ages for the oldest stars in the Milky Way, starting from our existing grids of state-of-the-art 3D model atmospheres and by tackling know issues in white dwarf crystallisation and convection physics.
For more information: contact Pier-Emmanuel Tremblay
To make an application, please complete the on-line forms linked from our Physics postgraduate admissions pages.