标题： 反氦原子光谱的精密测量 显示英文标题

标题： Precision spectroscopy of antiprotonic helium

摘要： 反氦，一种由氦核、电子和反质子组成的中性奇异三体系统，在欧洲核子研究中心的反质子减速器上由ASAUCSA合作组进行研究。 利用该系统中反质子能级的激光光谱以及与理论的比较，得到了反质子与电子质量比值的一个误差为3 ppb的结果。 这一结果与质子最精确测量值一致，并允许我们得出质子和反质子电荷和质量相等性的限制为2 ppb。 使用微波光谱学，反氦的超精细结构被测量到30 ppm。 预计实验改进将很快提供反质子磁矩的新值。 显示英文摘要

摘要： Antiprotonic helium, a neutral exotic three-body system consisting of a helium nucleus, an electron and an antiproton, is being studied at the Antiproton Decelerator of CERN by the ASAUCSA collaboration. Using laser spectroscopy of the energy levels of the antiproton in this system and comparison to theory, a value of the antiproton-to-electron mass ratio with an error of 3 ppb could be obtained. This result agrees with the most precise measurement of the value of the proton and allows us to extract a limit of the equality of the proton and antiproton charge and mass of 2 ppb. Using microwave spectroscopy, the hyperfine structure of antiprotonic helium has been measured to 30 ppm. Experimental improvements are expected to soon provide a new value for the magnetic moment of the antiproton.