Molecular Fractionation, the link with Solar System Small Bodies

Étudiant : EVANS Lucy

Directeur de thèse : VASTEL Charlotte (IRAP) et FONTANI Francesco (INAF-Arcetri)

Début de thèse : Novembre 2019

Groupe thématique : MICMAC

Several observations have shown that among the most abundant elements in the Universe, three of them, hydrogen, oxygen and nitrogen, present anomalous isotopic enrichments – i.e. abundances of the less abundant stable isotopes higher than those of the Proto-Solar nebula – in comets, carbonaceous chondrites and other pristine small Solar System bodies.How these enrichments took place and what the possible links are with the host environment and its past chemical history are still a mystery.The thesis project aims at measuring the isotopic ratios of the most abundant elements in dense Solar-like star-forming cores and compare them with both the isotopic values found in pristine small Solar system bodies and the Porto-Solar nebula value. To this end, I will use data obtained from several Large Programs of the group (SOLIS with IRAM-NOEMA and FAUST with ALMA) plus new observations gathered by myself and compare them with predictions of models developed by the AstroChemical Origins (ACO) team.
The thesis is part of the ACO network, whose ultimate goal is to reconstruct the early history of the Solar System by comparing presently forming solar-type planetary systems with its small bodies. The comparison will be based on the most advanced astrochemical knowledge, which will be developed by the interdisciplinary ACO team. (