How astrochemistry unravels our cosmic origins
Intervenant : Romane Le Gal
Astrochemistry, which strongly depends on the physical conditions of its environment, has started very shortly after the Big Bang and therefore represents an outstanding intermediary to study the chemical, physical and dynamical history of our Universe. In the recent years, major improvements in laboratory astrophysics and new generations of radio ground (ALMA, NOEMA, FAST), airborne and space (SOFIA, Herschel, JWST) telescopes, are opening a new age of the Astronomy discovery, in which Astrochemistry constitutes a keystone in the interpretation of the new chemical “big data” at our fingertips unveiling the molecular Universe. In order to extract all the power of the molecular line diagnostics it is of prime importance to fully understand how the molecules detected are formed, excited and destroyed in the different type of environments where they are observed. In this talk I will present how my research combines radioastronomical observations and astrochemical modeling fed by theoretical and experimental studies to better understand our chemical Universe and its history. In particular, I will highlight the potential to study molecular abundance ratios and especially isomer ratios, such as nuclear-spin state molecular ratios from low-mass protostar envelops to protoplanetary disks. The influence of grain-surface chemistry will also be emphasized. I will show how the study of nuclear-spin astrochemistry, while still in its infancy, promises a florescence of new probes for the Universe comprehension.