TY - JOUR

T1 - Homogeneity assessment of the SuperCam calibration targets onboard rover perseverance

AU - Madariaga, J. M.

AU - Aramendia, J.

AU - Arana, G.

AU - Castro, K.

AU - Gomez-Nubla, L.

AU - de Vallejuelo, S. Fdez-Ortiz

AU - Garcia-Florentino, C.

AU - Maguregui, M.

AU - Manrique, J. A.

AU - Lopez-Reyes, G.

AU - Moros, J.

AU - Cousin, A.

AU - Maurice, S.

AU - Ollila, A. M.

AU - Wiens, R. C.

AU - Rull, F.

AU - Laserna, J.

AU - Garcia-Baonza, V.

AU - Madsen, M. B.

AU - Forni, O.

AU - Lasue, J.

AU - Clegg, S. M.

AU - Robinson, S.

AU - Bernardi, P.

AU - Brown, A. J.

AU - Cais, P.

AU - Martinez-Frias, J.

AU - Beck, P.

AU - Bernard, S.

AU - Bernt, M. H.

AU - Beyssac, O.

AU - Cloutis, E.

AU - Drouet, C.

AU - Dromart, G.

AU - Dubois, B.

AU - Fabre, C.

AU - Gasnault, O.

AU - Gontijo, I.

AU - Johnson, J. R.

AU - Medina, J.

AU - Meslin, P. -Y.

AU - Montagnac, G.

AU - Sautter, V.

AU - Sharma, S. K.

AU - Veneranda, M.

AU - Willis, P. A.

PY - 2022/5/29

Y1 - 2022/5/29

N2 - The SuperCam instrument, onboard the Perseverance rover (Mars 2020 mission) is designed to perform remote analysis on the Martian surface employing several spectroscopic techniques such as Laser Induced Breakdown Spectroscopy (LIBS), Time-Resolved Raman (TRR), Time-Resolved Fluorescence (TRF) and Visible and Infrared (VISIR) reflectance. In addition, SuperCam also acquires high-resolution images using a color remote micro imager (RMI) as well as sounds with its microphone. SuperCam has three main subsystems, the Mast Unit (MU) where the laser for chemical analysis and collection optics are housed, the Body Unit (BU) where the different spectrometers are located inside the rover, and the SuperCam Calibration Target (SCCT) located on the rover's deck to facilitate calibration tests at similar ambient conditions as the analyzed samples. To perform adequate calibrations on Mars, the 22 mineral samples included in the complex SCCT assembly must have a very homogeneous distribution of major and minor elements. The analysis and verification of such homogeneity for the 5-6 replicates of the samples included in the SCCT has been the aim of this work. To verify the physic chemical homogeneity of the calibration targets, micro Energy Dispersive X-ray Fluorescence (EDXRF) imaging was first used on the whole surface of the targets, then the relative abundances of the detected elements were computed on 20 randomly distributed areas of 100 x 100 mu m. For those targets showing a positive Raman response, micro-Raman spectroscopy imaging was performed on the whole surface of the targets at a resolution of 100 x 100 mu m. The %RSD values (percent of relative standard deviation of mean values) for the major elements measured with EDXRF were compared with similar values obtained by two independent LIBS set-ups at spot sizes of 300 mu m in diameter. The statistical analysis showed which elements were homogeneously distributed in the 22 mineral targets of the SCCT, providing their uncertainty values for further calibration. Moreover, nine of the 22 targets showed a good Raman response and their mineral distributions were also studied. Those targets can be also used for calibration purposes of the Raman part of SuperCam using the wavenumbers of their main Raman bands proposed in this work.

AB - The SuperCam instrument, onboard the Perseverance rover (Mars 2020 mission) is designed to perform remote analysis on the Martian surface employing several spectroscopic techniques such as Laser Induced Breakdown Spectroscopy (LIBS), Time-Resolved Raman (TRR), Time-Resolved Fluorescence (TRF) and Visible and Infrared (VISIR) reflectance. In addition, SuperCam also acquires high-resolution images using a color remote micro imager (RMI) as well as sounds with its microphone. SuperCam has three main subsystems, the Mast Unit (MU) where the laser for chemical analysis and collection optics are housed, the Body Unit (BU) where the different spectrometers are located inside the rover, and the SuperCam Calibration Target (SCCT) located on the rover's deck to facilitate calibration tests at similar ambient conditions as the analyzed samples. To perform adequate calibrations on Mars, the 22 mineral samples included in the complex SCCT assembly must have a very homogeneous distribution of major and minor elements. The analysis and verification of such homogeneity for the 5-6 replicates of the samples included in the SCCT has been the aim of this work. To verify the physic chemical homogeneity of the calibration targets, micro Energy Dispersive X-ray Fluorescence (EDXRF) imaging was first used on the whole surface of the targets, then the relative abundances of the detected elements were computed on 20 randomly distributed areas of 100 x 100 mu m. For those targets showing a positive Raman response, micro-Raman spectroscopy imaging was performed on the whole surface of the targets at a resolution of 100 x 100 mu m. The %RSD values (percent of relative standard deviation of mean values) for the major elements measured with EDXRF were compared with similar values obtained by two independent LIBS set-ups at spot sizes of 300 mu m in diameter. The statistical analysis showed which elements were homogeneously distributed in the 22 mineral targets of the SCCT, providing their uncertainty values for further calibration. Moreover, nine of the 22 targets showed a good Raman response and their mineral distributions were also studied. Those targets can be also used for calibration purposes of the Raman part of SuperCam using the wavenumbers of their main Raman bands proposed in this work.

KW - Mars2020

KW - Perseverance rover

KW - SuperCam calibration target

KW - Elemental homogeneity

KW - Mineral homogeneity

KW - Uncertainties

KW - CHEMCAM INSTRUMENT SUITE

KW - GALE CRATER

KW - MARS

KW - SPECTROSCOPY

KW - PROPOSITION

KW - UNIT

U2 - 10.1016/j.aca.2022.339837

DO - 10.1016/j.aca.2022.339837

M3 - Journal article

C2 - 35569848

VL - 1209

JO - Analytica Chimica Acta

JF - Analytica Chimica Acta

SN - 0003-2670

M1 - 339837

ER -