Knowledge Bank

We report on first applications of a Laser Photolysis-Molecular Beam-Fourier Transform Microwave (LP-MB-FTMW) spectrometer in the spectral region 8 to 40 GHz, constructed for investigations of rotational spectra of free radicals. The experimental set-up consists of a near semi-confocal Fabry-Perot type microwave resonator mounted in a stainless steel vacuum chamber. The cavity resonance can be adjusted by moving the spherical mirror. A current actuated slit nozzle value is situated near the center of the flat mirror, just above the microwave antennas. The performance of the spectrometer was optimized by recording $SO(X3\Sigma )$ microwave spectra. SO radicals were produced by 193 nm photodissociation of $SO2$ in a pulsed supersonic free jet expansion in Ar. Additionally, first results of the LP-MB-FTMW detection of the $C2H3O$ (vinoxy) and of $CF2$ radicals will be presented.