Chirp-corrected, nanosecond Ti:sapphire laser with 6 MHz linewidth for spectroscopy of antiprotonic helium

A nanosecond titanium sapphire laser with spectral linewidth Gamma(pl) similar to 6 MHz and pulse energy of 50-100 mJ was demonstrated by using an intracavity electro-optic modulator to correct the frequency chirp in the output beam. The laser was referenced against a femtosecond frequency comb and used to measure the 6s-8s (F=4) two-photon transition frequency of Cs with a precision of 1.4 parts in 10(9). (C) 2009 Optical Society of America