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Abstract

Pulsed valve jet-cooled radical setup
Pulsed valve jet-cooled radical setup: excimer laser fires toward (or across) the pulsed valve jet expansion to create radicals that are cooled in the expansion.

Free radicals are produced by excimer laser flash photolysis of a suitable precursor inside the nozzle of a pulsed slit jet and cooled by supersonic expansion from the slit. The infrared spectra of the radicals are then probed by a single-frequency color-center laser. This technique has been tested on the NH2 radical.