CO laser emission at 5 μm was detected when SO2 and CFBr3 were flash photolyzed in the vacuum ultraviolet above 165 nm. Over 40 vibrational–rotational transitions ranging from Δv = 2 → 1 to 14 → 13, with the exception of those between 8 → 7 and 11 → 10, were identified. The CO emission is believed to result from the O + CF reaction: (Formula Presented.) The vibrational population of the CO has been measured by means of a CO laser resonance absorption method. The CO was found to be vibrationally excited to v = 24 with a vibrational temperature of about 1.4 × 104°K. The “surprisal analysis” of the observed CO distribution showed the possible occurrence of a minor process (presumably O + CFBr) that generated vibrationally colder CO. The effects of various additives on the CO emission were also examined. The addition of CO2 to a D2‐SO2‐CFBr3‐He mixture resulted in a simultaneous osciallation at 3.6, 5, and 10.6 μm due to DF, CO, and CO2, respectively. Additionally, the utilization of the O + CFn (n = 1, 2, 3) reactions as F‐atom sources for HF‐laser operation in flash‐initiated systems were demonstrated.