New results for the epsilon-expansion of certain one-, two- and three-loop Feynman diagrams
A.I. Davydychev, M.Yu. Kalmykov
对于某些维度调节的单环图,二环图和三环图,研究构建epsilon-expansion的问题以及结果的分析延续。 在一些例子中,可以计算epsilon-expansion的任意术语。 对于更复杂的情况,在epsilon中只获得几个更高的术语。 除了单环二点和三点图外,例子还包括双环(主要是空壳)传播器型图和三环真空图。 作为副产品,建立了一些涉及克劳森函数,广义日志-正文积分和某些欧拉-扎吉尔总和的新关系,并提出了一些参数1/4的超几何函数的有用结果。
For certain dimensionally-regulated one-, two- and three-loop diagrams, problems of constructing the epsilon-expansion and the analytic continuation of the results are studied. In some examples, an arbitrary term of the epsilon-expansion can be calculated. For more complicated cases, only a few higher terms in epsilon are obtained. Apart from the one-loop two- and three-point diagrams, the examples include two-loop (mainly on-shell) propagator-type diagrams and three-loop vacuum diagrams. As a b...