Optical clockwork for a precision measurement in hydrogen*

Ultracold trapped hydrogen ($<$100 micro kelvin) provides an excellent environment for spectroscopy and an opportunity to extend the experimental precision of the Lamb shift and the Rydberg constant. We will describe a newly constructed array of stable laser systems (ring dye laser, prismless Ti:saph femtosecond comb, synchronized diode lasers) designed to measure the ratio of the frequency of the 2S-8S transition to the frequency of the 1S-2S transition in hydrogen.