Order Alpha Squared Corrections to Energy Levels and Decay Rates of Positronium (Physics)

正电子素是正电子-电子的束缚态。 的 正电子素的结构几乎完全受QED控制; 强和弱修正与电动修正相比是小的 方面的影响. 正铬也可以达到高精度 实验 因此，正电子素是一个理想的实验室， 研究QED和量子场的束缚态形式 理论 正电子素中主要的物理量是 能级和衰变率。 几种能级分裂 的n=1和n=2的状态已被测量的不确定性， 几MHz的数量级。 目前的理论评价，这些 分裂与实验一致，m（α）6 = 18.7 MHz尚未计算。 n=1自旋单态和自旋 还测量了三重态衰变率。 自旋三重态 利率是几个标准差远离目前 理论值。 显然需要扩大理论上的 电子偶素的能级和衰变率的计算 阿尔法的另一种力量 建议计算一些 这些更正，并在计算 他人 特别是计划完成计算 n=1和n=2的正电子素能级通过阶m（alpha）6。 在这个层次上比较实验和理论将提供一个 详细测试的束缚态形式主义和量子电动力学。

Positronium is the positron-electron bound state. The structure of positronium is governed almost completely by QED; strong and weak corrections are small compared to electrodynamic effects. Positromium is also accessible to high precision experiments. Thus positronium is an ideal laboratory for studying QED and the bound state formalism in quantum field theory. The main quantities of physical interest in positronium are energy levels and decay rates. Several energy level splittings of n=1 and n=2 states have been measured with uncertainties on the order of a few MHz. Present theoretical evaluations of these splittings agree with experiment, with terms of order m(alpha)6 = 18.7 MHz still uncalculated. The n=1 spin-singlet and spin triplet decay rates have also been measured. The spin-triplet rate is several standard deviations away from the present theoretical value. There is an evident need to extend the theoretical calculations of energy levels and decay rates in positronium by another power of alpha. It is proposed to calculate some of these corrections and to make progress on the calculation of others. In particular it is planned to complete the calculation of n=1 and n=2 positronium energy levels through order m(alpha)6. Comparison of experiment and theory at this level will provide a detailed test of the bound state formalism and of QED.