TURN-BY-TURN MEASUREMENTS AT THE KEK-ATF

The ATF damping ring has been upgraded with new read-out electronics for the beam position monitors (BPM), capable to acquire the beam orbits on a turn-by-turn basis, as well as in a high resolution averaging mode. The new BPM system allows to improve optic corrections and to achieve an even smaller vertical emittance (<2pm). Experimental results are presented based on turn-by-turn beam orbit measurements in the ring, for estimating the functions and dispersion along the lattice. A fast method to measure spectral line amplitude in a few turns is also presented, including the evaluation of chromaticity.