COMPARISON OF THEORY WITH ATOMIC OXYGEN RADIANCE DATA FROM A ROCKET FLIGHT

Results obtained from a state-of-the-art now and radiation model are c ompared with vacuum-ultraviolet radiance data obtained from the recent Bow Shock 2 Flight Experiment. An extensive data set of atomic-oxygen resonance radiance measurements was obtained in flight for a re-entry speed of 5 km/s between the altitudes of approximately 65-85 km. A de scription of the NO photoionization cell used, the data, and the inter pretation of the data will be presented. A new radiation model appropr iate to the night conditions of Bow Shock 2 is proposed. Comparison of theory with the data shows that at high altitudes the flow is optical ly thin. At altitudes lower than about 75 km the flow is optically thi ck and the disagreement between theory and experiment is attributed to the inadequate treatment of photon escape mechanisms from the shock l ayer.