# LIBS (Laser-Induced Breakdown Spectroscopy) pour l'observation martienne

Abstract : ChemCham is onboard the Mars Science Laboratory (MSL) mission, which was launched the 26$^{th}$ November 2011. This instrument uses the LIBS (Laser-Induced Breakdown Spectroscopy) technique to study the geochemistry of the Martian surface. This technique is used for the first time for the Space and Planetary exploration. In LIBS technique a pulsed laser beam is focused on a target, creating a plasma. The spectral analysis of the plasma light is collected to observe the characteristic emission lines of the elements present in the sample. This work contributes to the preparation of the scientific returns of the MSL mission but also of ChemCam, with four principal axes : - identification and characterization of the significant elemental lines, - test of the method used to distinguish rocks with these measurements, - study of the capacity to analyze the alteration coating on rocks, - data analysis to extract informations about the structure and/or composition of rocks A ground station was developed in order to be representative of the Martian surface conditions. An elemental lines database specific of ChemCam and Mars is performed, with up to 1300 lines. Several experimental studies let us to characterize some of the ChemCam capabilities. First, rocks classification is successful whatever the kind of the sample. Some parameters were studied to understand their influence on the classifications. Then, quantitative analysis with ChemCam are feasible, not only using statistical methods. We show that ChemCam is able to analyze the composition of the alteration coating before the one from the unaltered rock, deeper. It is also able to make some differences between several kinds of basalts with their texture and matrix, and between several kinds of clays, looking at their internal structure.
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https://tel.archives-ouvertes.fr/tel-00717266
Contributor : Williams Exbrayat <>
Submitted on : Thursday, July 12, 2012 - 2:09:57 PM
Last modification on : Thursday, October 15, 2020 - 4:07:23 AM
Long-term archiving on: : Thursday, December 15, 2016 - 10:15:38 PM

### Identifiers

• HAL Id : tel-00717266, version 1

### Citation

Agnès Cousin. LIBS (Laser-Induced Breakdown Spectroscopy) pour l'observation martienne. Instrumentation et méthodes pour l'astrophysique [astro-ph.IM]. Université Paul Sabatier - Toulouse III, 2012. Français. ⟨tel-00717266⟩

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