Fig. 2: The result of CO2 photolysis experiments.
From: Synthesis of 13C-depleted organic matter from CO in a reducing early Martian atmosphere
Solid circles show the CO fraction produced from CO2. Red circles show the carbon isotope composition of CO normalized against that of the initial CO2 (δ13C-CO = ((13CO / 12CO) / (13CO2 / 12CO2) – 1) × 1,000‰). Error bars represent external reproducibility (standard deviation: n = 10) of the mass spectrometric analysis determined by replicated analysis of in-house standard CO gas. Red and black lines represent the calculated isotope ratio and CO fraction, respectively, assuming fractionation factors for CO2 photolysis (α1 = 0.871) and for CO oxidation (α2 = 1.0074).
