Laser-enhanced ionization spectrometry of the OH radical in a flame

The OH radical produced in an air-acetylene flame resonantly was excited by ultraviolet (UV) laser in the 2824-2838 A region. Enhanced ionization signals were detected. The spectral band of the OH radical was obtained in the vicinity of UV 2830 A, corresponding to a X 2 π→A 2 Σ(υ=0→1) transition of OH. More than twenty spectral lines were measured, which coincide with previous data obtained from flame emission spectroscopy. This method has provided a way of radical determination and flame diagnostics