Precision Tests of Fundamental Interactions

Laser spectroscopy of antihydrogen

Laser spectroscopy of antihydrogen: In a series of the papers published in Nature, the ALPHA collaboration reported the first-ever laser spectroscopy of antimatter atoms. Over the past several decades, laser spectroscopy of the ordinary hydrogen atom has reached exceedingly high accuracies to the level of 4x10-15 level. Now ALPHA has achieved laser measurements in antihydrogen, with an initial precision of  2x10-10, which was subsequently improved to 2x10-12. The latter is the most precise direct measurement of antimatter properties, and represents a test of matter-antimatter symmetry, known as CPT symmetry, with a parts-per-trillion precision. The results attracted significant attention both from the scientific community and the general public.