Energy transfer from O(D-1) to O-2 is the main source of O-2(b(1)Sigma(+)(g)) in vibrational levels upsilon = 0 and 1 in the Earth's thermosphere. Knowledge of the relative yields for O-2(b(1)Sigma(+)(g)) production in upsilon = 0 and 1 is essential for a reliable interpretation and modeling of the O-2 atmospheric band emissions (b(1)Sigma(+)(g) = X-3 Sigma(-)(g)) from these two vibrational levels. We report laboratory measurements of the relative yields at room temperature. In the experiments, O-2(b(1)Sigma(+)(g), upsilon = 0, 1) is generated by O(D-1) + O-2 collisions following partial photodissociation of O-2 at 157.6 nm. O-2(b(1)Sigma(+)(g), upsilon = 0, 1) emission detection is used to monitor the temporal evolution of the vibrational level populations. The measured fractional yield for upsilon = 1 is 0.8 +/- 0.1, in contrast with the results of previous studies that indicated dominant O-2(b(1)Sigma(+)(g), upsilon = 0) production. A revision is warranted of the values used for these relative yields in atmospheric models. (C) 2014 AIP Publishing LLC.
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