Dual Comb Spectrometer for the Determination of Stable Isotopic Ratios of Atmospheric CO₂ with Sub-Permille Precision at Atmospheric Pressure.

ABSTRACT: We present a mid-infrared dual comb spectrometer for the precise determination of the isotopic ratio of the stable CO₂ isotoplogues ¹²C¹⁶O₂ and ¹³C¹⁶O₂ under atmospheric pressure. The spectrometer is based on electro-optic intensity modulation at 1550 nm wavelength and subsequent wavelength flexible conversion to the mid-infrared. Here, the fundamental absorptions of CO₂ in the ν₃ band around 4.3 μm wavelength (2300 cm^-1) were accessed to achieve the needed sensitivity to investigate the isotopic composition at atmospheric concentrations. The high spectral resolution of 0.004 cm^-1 and spectral coverage of 8 cm^-1 enable the measurements of the three most abunda

SUBMITTER: Goldschmidt J 

PROVIDER: S-EPMC12756849 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature