QUANTUM BEAT SPECTROSCOPY OF JET-COOLED TRANSIENT RADICALS GENERATED BY A PULSED ELECTRICAL-DISCHARGE

Using a pulsed electrical discharge nozzle, we have extended quantum b eat spectroscopy to radicals in a molecular beam. To demonstrate the m ethod, we studied three prototypical systems: the diatomic radical OD, the radical van der Waals complex Ar OD and the polyatomic vinery rad ical (CH2CHO). In all three cases hyperfine quantum beats were observe d and identified on the fluorescence decays from excited electronic st ates with or without an external magnetic field. The application of th is method to other radical systems is discussed.