12 avril 2021
Context: Noble gases in Earth’s interior provide a strong constraint on the timing of our planet’s growth and the compositions of its building blocks. Xenon isotopes in the mantle have a different isotopic signature than those in our atmosphere. While the mantle’s Xe was sourced from material close to the Earth during its growth, atmospheric Xe included a component that was delivered by comets during the giant planets’ instability. We propose to build a suite of planet formation models that reproduce the inner Solar System, focusing on the timing of cometary bombardment under different assumptions. We will use laboratory measurements of Xe isotopes in different meteorite samples to establish the nature of the potential building blocks of the terrestrial planets. Finally, we will use these measurements (supplemented by values from the literature) to constrain the possible growth history of Earth and dynamical history of the Solar System.
PhD project: The student will spend roughly two-thirds of their effort building and refining models of Solar System formation, with a specific focus on the source material incorporated into the Earth and the timing of cometary impacts. The other one-third will be dedicated to laboratory measurements of noble gases in selected meteorites and their analysis. The student will be housed in the Laboratoire d’Astrophysique de Bordeaux (advised by Sean Raymond) and will collaborate with Guillaume Avice at the Institut de Physique du Globe de Paris and Eric Gilabert at the Centre d’Etudes Nucléaires de Bordeaux-Gradignan.
Qualifications: The applicant should have a master’s degree in astrophysics or a related field. We are especially interested in candidates with expertise in numerical methods and computing and an interest in laboratory measurements.
Full scientific details can be downloaded here:
To apply: Please send a CV and a short statement of interest to Sean Raymond – sean.raymond (at) u-bordeaux.fr – by May 15th.