Grating tuned Ti:Sa laser for in-source spectroscopy of Rydberg and autoionizing states

Due to the large absorption cross section for optical transitions into Rydberg and autoionizing states compared to non-resonant ionization, these states are of particular interest for use in efficient laser resonance ionization excitation schemes as used in Resonant Ionization Laser Ion Sources (RILIS). In order to identify these atomic states extensive laser spectroscopy has to be performed. The lasers employed at TRIUMF’s laser ion source are birefringent filter tuned titanium:sapphire (Ti:Sa) lasers which are designed for long term frequency stability rather than continuous tuning. The design and characteristics of a grating tuned, high repetition rate, pulsed Ti:Sa laser for spectroscopy applications are presented. This laser allows fast scans of up to 40 THz with a laser linewidth of approximately 6 GHz. First tests were performed by scanning across the Rydberg series of gallium.