ABSTRACT: A test of time dilation in special relativity has been performed using laser spectroscopy on fast ions at the heavy-ion storage-ring TSR in Heidelberg. The Doppler-shifted frequencies of a two-level transition in Li+ ions at v = 0.064 c have been measured in forward and backward direction to a frequency accuracy of 1 × 10^-9 using collinear saturation spectroscopy. The result confirms the relativistic Doppler formula and sets a new limit of 2.2 × 10^-7 for deviations from the time dilation factor. An improved experiment has just been completed at TSR and a new measurement at the ESR storage ring at v = 0.35 c is currently started. We will report on these developments, and on the constraints these experiments put on CPT and Lorentz-violating extensions of the Standard Model.

Contact: Luis Orozco