The Collinear Resonance Ionization Spectroscopy (CRIS) experiment at ISOLDE, studies exotic nuclei by resonantly ionizing a bunched atomic beam in a region of ultra high vacuum. This method has sufficient sensitivity and resolution to measure the hyperfine structure and isotope shift at the extremes of isospin where typical production rates drop to 1 atom/s. The technique also offers the ability to purify an ion beam and select long-lived isomeric states (>1ms) from the ground state, which can be subsequently studied by decay spectroscopy or mass spectrometry experiments. The CRIS experiment was successfully commissioned in 2012 and has measured the hyperfine structure and decay properties of neutron-deficient and neutron-rich isotopes of francium. This talk will describe the experimental methodology, recent results and future outlook.
