The temporal variation of chemiluminescence emission from OH * (A 2 Σ + ) and CH * (A 2 Δ) in reacting Ar-diluted H 2 /O 2 /CH 4 , C 2 H 2 /O 2 and C 2 H 2 /N 2 O mixtures was studied in a shock tube for a wide temperature range at atmospheric pressures and various equivalence ratios. Time-resolved emission measurements were used to evaluate the relative importance of different reaction pathways. The main formation channel for OH * in hydrocarbon combustion was studied with CH 4 as benchmark fuel. Three reaction pathways leading to CH * were studied with C 2 H 2 as fuel. Based on well-validated groundstate chemistry models from literature, sub-mechanisms for OH * and CH * were developed. For the main OH * -forming reaction CH + O 2 = OH * + CO, a rate coefficient of k 2 = (8.0 ± 2.6) × 10 10 cm 3 mol −1 s −1 was determined. For CH * formation, best agreement was achieved when incorporating reactions C 2 + OH = CH * + CO (k 5 = 2.0 × 10 14 cm 3 mol −1 s −1 ) and C 2 H + O = CH * + CO (k 6 = 3.6 × 10 12 exp(−10.9 kJ mol −1 /RT) cm 3 mol −1 s −1 ) and neglecting the C 2 H + O 2 = CH * + CO 2 reaction.