Improving the Spectral Coverage and Resolution of the ISOLDE RILIS

This thesis concerns applications and developments of the Resonance Ionization Laser Ion Source (RILIS) at CERN-ISOLDE for ion beam production and laser spectroscopy. Laser developments, including the first operation of a grating-tuned Ti:sapphire combined with a thick etalon for linewidth reduction, the construction and characterization of a seeded Ti:sapphire ring cavity laser and the first demonstration of a Raman laser in the blue spectral range are presented. In-source laser spectroscopy on Dy isotopes has been performed, providing a valuable insight into the nuclear charge radii systematics near proton number $Z=64$. This work also illustrates the resolution limit imposed by Doppler-broadening of the atomic spectral lines inside the ion source. Addressing this limitation, the Doppler-free 2-photon ionization technique has been developed, leading to its first successful "in-source" application. The future of this approach to significantly increase the spectral resolution of RILIS is discussed.