Development of a highly intense state-selected CH radical beam source for the study on the collision energy dependent reaction dynamics

A velocity-variable highly intense pulsed supersonic CH (X2Π) radical beam source was newly developed for the study on the collision energy dependent reaction dynamics of the state-selected CH radical. CH radicals were state-selected by an electrostatic hexapole field. The focusing curves and the CH flux intensities for the ∣J, Fi, M〉 states were measured by a saturated laser-induced fluorescence spectroscopy. As a demonstration, the rotational state dependence of the reaction cross section of CH + O2 → OH(A) + CO reaction was determined at the collision energy of 0.06 eV.