Characterization of laser-induced plasmas under simulated conditions of selected celestial bodies

• Applicant: Igor B. Gornushkin, Ph.D.
• Subject Area: Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas ; Analytical Chemistry ; Mineralogy, Petrology and Geochemistry
• Term: since 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 511798845

The exploration of near celestial bodies represents a persisting interest for various techniques/research fields. This involves geological survey, particularly the elemental analysis of surface of, e.g., Mars, Moon and even of asteroids. For this purpose, various strategies were developed, among which the laser-induced breakdown spectroscopy (LIBS) technique has proven itself as one of the most convenient approaches. The utilization of LIBS in remote and even stand-off applications is enabled from its essence, focusing a laser pulse on the sample surface, ablating a fraction of the target material, inducing a plasma, and collecting its optical emission for further spectroscopic investigation. However, laser-matter interactions and the consequent laser ablation is significantly influenced by physical/chemical matrix effects of the examined sample and experimental parameters, incl. the ambient conditions (buffer gas in laboratory, atmosphere, or ultra-high vacuum on celestial body surface) on the considered celestial bodies. To provide reliable LIBS analysis, it is mandatory to understand the processes of ablation, plasma formation and its evolution. The main scope of the project is to describe mentioned processes with respect to the ambient conditions of said celestial bodies. The novelty of the project can be summarized as follows. A) Novel approaches in the correlation of characteristics signals (e.g., showing plasma shape and heterogeneity, speed of the shockwave expansion) for more accurate description (e.g., temperature and electron density distributions within the plasma bulk) of spatial-temporal evolution of LIP model and their comparison with numerical models. B) A machine-learning based approach enabling the transfer of the LIBS data obtained under Earth-like conditions to Mars- and Moon-like conditions that goes beyond the current state of the art. C) Innovative application of time-resolved FTIR spectrometry for LIP characterization that provides detailed information about the atomic and molecular species forming in the ablation plasma (with ability to resolve the rotation vibration transitions of multiple overlapping molecular bands as well as the hyperfine structure of atomic spectral lines). D) Plasma model that accounts for chemical transformations in the plasma plume and allows the prediction of plasma emission spectra, which are directly comparable to experiment, is unique and novel. It will allow the optimization of complexly intertwined experimental parameters without making tedious and time-consuming optimization experiments.

• DFG Programme: Research Grants
• International Connection: Czech Republic
• Co-Investigator: Dr. Jens Riedel
• Cooperation Partners: Petr Kubelik, Ph.D.; Professor Dr.-Ing. Pavel Porizka, Ph.D.