G/R ratio for each subslit and offset spectrum for comet 103P/Hartley 2. The range of nucleocentric distances covered by each point and the error on the G/R ratio are represented. The model-calculated G/R ratios as a function of projected distance are plotted. An H₂O production rate of 1.18 × 10²⁸ s^-1 and 0.5% CO as relative abundance were used with different seeing values and different CO₂ relative abundances. The fits give the CO₂ relative abundance of the comet. The black dash-dotted curve represents the calculated G/R ratio not accounting for collisional quenching with 15% CO₂ relative abundance. The pentagon symbols are the data points for the offset observations.