Resonance ionization spectroscopy on a fast atomic beam

Resonance Ionization Spectroscopy in collinear geometry has been successfully applied to a fast beam of Yb atoms. The atoms were excited stepwise into a Rydberg state by pulsed laser light, ionized in an electrical field and deflected onto a secondary electron detector. The efficiency was 1.10-5 detected ions per incoming atom on a background from collisional ionization of 1.10-8. The technique has been exploited for the measurement of hyperfine structures and isotope shifts of unstable Yb isotopes, in particular 157Yb, 159Yb and 175Yb. (Author)