TEST OF SPECIAL RELATIVITY IN AN ION STORAGE-RING

An accurate measurement of the Doppler effect in collinear laser spect roscopy has been performed at the TSR storage ring with electron coole d Li-7(+) ions at beta = 0.064. This experiment is a sensitive test of the gamma = (1 - beta(2))(-1/2) factor(beta = upsilon/c) in the speci al theory of relativity. The Doppler shifted frequencies of the moving Li-7(+) ions are compared with calibrated molecular lines at rest. Th e frequencies at rest for the Li-7(+) ions are known from independent measurements. The Doppler shifted frequencies in the collinear experim ent have been measured with a precision of Delta v/v = 6 x 10(-9), mai nly limited by the signal width of the resonance. A corresponding uppe r limit of 8 x 10(-7) is deduced for any deviation of the time dilatat ion factor gamma in special theory of relativity. A still higher accur acy is expected with a laser cooled ion beam. If such a beam is simult aneously subjected to RF bunching, the particle velocity and phase are exactly known. With an additional high resolution laser frequency mea surement an improvement of at least one order of magnitude may be achi eved.