Thesis title: Molecular fractionation, the link with the Solar System small bodies.

Supervisor: Prof. C. Vastel (University Paul Sabatier Toulouse 3 - IRAP)

Co-Supervisor: Dr. F. Fontani (INAF)

Recruitment Institution: INAF - Osservatorio Astrofisico di Arcetri, Firenze, Italy

Doctoral School: University Paul Sabatier Toulouse 3 - IRAP, France

Mobility: The ESR will spend the first 12 months at IRAP, the following 18 months at INAF, and the last 6 months at IRAP.

Eligibility: European and non-European students who not have resided or carried out their main activity (work, studies, ect.) in Italy for more than 12 months in the 3 years immediately before the recruitment date.

Thesis description:

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 are the possible links 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 Proto-Solar Nebula value. To this end, the ESR will use data obtained from several Large Programs of the group (SOLIS with IRAM-NOEMA and FAUST with ALMA) plus new observations gathered by the ESR, and compare them with the predictions of models developed by the 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.