Optimizing Calibration Transfer for Laser-Induced Breakdown Spectroscopy (LIBS): A Multi-Instrument Investigation Across Atmospheric and Laser Power Variations

Abstract

Laser-Induced Breakdown Spectroscopy (LIBS) analyzes elemental composition by measuring plasma emissions from laser-ablated samples. This study develops a universal calibration model for LIBS applications across Earth (760 Torr), Mars (7 Torr CO2), and vacuum (<1 Torr) conditions, with laser energies ranging from 3 to 9 mJ. Using 2,157 geological standards analyzed across four LIBS systems (SuperLIBS, ChemLIBS, and pLIBS Z300/Z903), we evaluate the performance of Partial Least Squares (PLS) regression through four validation scenarios, incorporating data from current Mars rover LIBS instruments (ChemCam and SuperCam) and their full and onboard calibration target sets. To account for atmospheric effects on plasma formation, we implement Piecewise Direct Standardization (PDS), a calibration transfer technique that mathematically adjusts spectral responses between different environmental conditions. The comprehensive calibration set developed across various LIBS setups provides crucial insights into prediction accuracy under Martian conditions while establishing a quantitative framework for LIBS applicable to diverse planetary environments, from Venus to airless bodies.