Knowledge Bank

Relative quantum yields of 557.7 nm radiation from the $ ^{1}S$ metastable of atomic oxygen have been measured from the photolysis of $CO2$ at wavelengths between 108 nm and 116 nm. The light source used gave multiline emission between 106 nm and 130 nm. Individual lines were chosen using a 1m vacuum monochromator. Light from the unit slit of the monochromator passed into a photolysis cell; this cell was cooled by a dry ice slush bath to reduce quenching of metastable $\mathrm{<mrow\; data-mjx-texclass="ORD">1</mrow>}S$ oxygen atoms. Emission from the chamber was detected using a photomultiplier and recorded using photon counting techniques.