Highly efficient and selective laser ion source by three-step resonant laser ionization

Resonance ionization of atoms confined in a hot cylindrical cavity is a very efficient and selective technique for trace analysis. Several applications of this method have been tested or are presently under investigation. An efficiency of 14% was obtained for technetium. An efficient path for rnance ionization of tin was found, leading to an autoioniing state at 59375.9 cm1. The high efficiency makes the baer ion source suitable for trace analysis of actinides in the environment. In all cas surface-ionized background has to be suppresoed to avoid isobaric interferences. Therefore a new laser ion source has been developed with a cavity made ofextremely pure pyrolytically coated graphite.