Missions

This project concerns the evolution of the icy grains of the dense molecular clouds from their collapse to the evolution of the solar nebula until the formation of a protoplanetary disk. This evolution is simulated at low pressure (10-9 mbar) and low temperature (12K-77K) by preparing an icy grain analogue. This analogue is then altered by different sources of irradiation (UV photons, electron or ion bombardment) to which it could have been subjected during its formation within the dense cloud and in the cold parts of the protoplanetary disk. Once altered, the icy grain analogue is slowly heated to simulate its evolution towards warmer areas within the disk. Some of the molecules formed during the first alteration phase sublime, enriching the gas phase. The most refractory molecules form an organic residue at 300K, analogous to what could have been found on the surface of certain grains of the protoplanetary disk. This residue is called a pre-accretionary organic matter analogue.
This is an innovative and unique project at the global level, which will be a key piece of equipment for GANIL and CIMAPand open new doors for different scientific communities, as part of the CIMAP-CIRIL hosting mission at the GANIL beamlines. The first objective will be to study the effects and potential synergies of irradiation by up to 3 beams on ice composed of simple molecules (H2O, CH3OH, NH3). These results will be compared with the experiments carried out so far with a single irradiation source. Other simple molecules such as CO, CO2, H2S, SO2 will complete the inventory to try to better match the observed ices. The volatile organic compounds present in the gas phase (in situ analysed by GC-Orbitrap) in collaboration with the PIIM laboratory (Aix-Marseille), as well as the refractory organic compounds will be analyzed by high-resolution mass spectroscopy to determine their composition and the chemical reactivity induced by these modifications. By crossing these analyses, we will try to establish the chemical links that may exist between the gas and solid phases.
The second objective is to test the radioresistance of complex organic molecules with the MIRRPLA platform. If they are produced during the irradiation of ices containing simple molecules, it is essential to know whether they will be able to survive on time scales corresponding to the different stages of the formation of our solar system.The third objective will be to simulate the evolution the samples formed in post-accretionary conditions. Indeed, once formed, these residues (cometary material for example) are continuously irradiated and their composition will therefore evolve over time. The results obtained can be compared to analyses of extraterrestrial objects (returns of samples or carbonaceous chondritic meteorites).
The third objective will be to evolve the samples formed in simulated post-accretional conditions. Indeed, once formed, these residues (cometary material for example) are continuously irradiated and their composition will therefore change over time. The results obtained can be compared to analyzes of extraterrestrial objects (sample returns or carbonaceous chondritic meteorites).
The request is made within the framework of the PEPR ORIGINS - MIRRPLA

Activities

-Take in charge commissioning of a new MIRRPLA multibeam platform ( mounting, vacuum tests, test of electron gun, UV lamp, ion source….)
-In situ measurements of energetic processing (ions, electrons, photons) of astrophysical ices (infrared spectroscopy and mass spectrometry like QMS/Orbitrap)
The recruitment is made within the framework of the PEPR ORIGINS - MIRRPLA


-Supervise master and PhD students.
-Participate in ion beam irradiation campaign at GANIL (France), GSI (Germany) or ATOMKI (Hungary).
-Data analysis and interpretation of experimental results in the context of astrophysics.
- Present results at conferences and write publications

Skills

The candidate must hold a PhD in physics, physical chemistry, chemistry or analytical chemistry with a maximum of 7 years of experience after the PhD.
The ideal candidate must have a strong background in laboratory astrophysics or a related domain, in molecular physics, collision physics, infrared spectroscopy, mass spectrometry and data processing skilles. Knowledge of orbitrap technique will be added value. The candidate must speak English fluently and demonstrate organizational skills as she/he will master multiple activites.

Work Context

"Where do we come from" is one of the most fascinating open questions in science and philosophy. How did life appear, what is the origin of organic matter in the universe? Could life also emerge on worlds other than our Earth? Complex organic molecules have indeed been observed in space (comets, meteorites, molecular clouds). In 2023, France launched the PEPR "Origins" (life and universe) led by CNRS, to answer these questions [https://pepr-origins.fr/]. Understanding the origin of primitive organic matter during the formation and evolution of the solar system is fundamental since the contribution of extraterrestrial organic matter via asteroids and comets is one of the possible sources of organic matter on the primitive Earth. The unique MIRRPLA multibeam irradiation platform (UV photons, keV electrons and keV-GeV ions delivered by the GANIL-Grand Accélérateur National d'Ions Lourds, Caen France) to simulate the effects of radiation in cold space environments is under construction. As part of the thesis, the first experiments with an infrared spectrometer and a cold head to prepare ice layers made up of small molecules or mixtures will be carried out. Complex organic molecules formed during irradiation and/or heating of ice layers will be detected by gas chromatography and in situ mass spectrometry.
The candidate will join the Materials, Defects, Irradiation (MADIR) team at CIMAP, the latter is a multidisciplinary research laboratory where scientific fields range from ion-matter interaction to materials for lasers, photonics and electronics. CIMAP is located near different ion beam lines of GANIL - a unique tool to study ion beam interactions with matter.

The position is located in a sector under the protection of scientific and technical potential (PPST), and therefore requires, in accordance with the regulations, that your arrival is authorized by the competent authority of the MESR.

Constraints and risks

Short periods of travel in France and abroad are to be expected. Working in an INB (Installation Nucléaire de Base) where certain areas are restricted (radiological surveillance). Chemical and radiological risks.

Additional Information

Possiblity of twelve months extension