Intensities in the Atmospheric Oxygen (Intercombination) Bands

Abstract

WE have made exact intensity measurements of the A group of the absorption bands of oxygen at λ7600 A. with the aid of the ‘raster’ method of Frerichs,¹ using a 6.4 metre concave grating, infra-red sensitive plates, and three different lengths of light path, respectively 14, 33, and 60 metres. It was found that the exponential absorption law J = J₀e−^kd holds for these absorption lines; for the 33 metre light path, assuming that the peaks of our photograms can be identified with the true absorption co-efficient, we find for the strongest line an absorption J₀ − J/J₀ of 27 per cent.