Calculation of Feynman diagrams from their small momentum expansion
Calculation of Feynman diagrams from their small momentum expansion
复制标题
根据小动量展开计算费曼图
DOI：
10.1007/bf01560102
复制
发表时间：
1994
期刊：
影响因子：
--
通讯作者：
O. Tarasov
中科院分区：
文献类型：
--
作者：
J. Fleischer;O. Tarasov
提出了一种计算费曼图的新方法。它包括建立一个泰勒级数展开的外动量平方（一般多变量）。泰勒系数是由原图通过求导和外动量为零得到的，这意味着极大的简化。证明了对原级数进行解析延拓，可以得到全切面上费曼积分的高精度数值。为此目的，保角映射和随后的recrimation通过Padé逼近或莱文变换。
A new powerful method to calculate Feynman diagrams is proposed. It consists in setting up a Taylor series expansion in the external momenta squared (in general multivariable). The Taylor coefficients are obtained from the original diagram by differentiation and putting the external momenta equal to zero, which means a great simplification. It is demonstrated that it is possible to obtain by analytic continuation of the original series high precision numerical values of the Feynman integrals in the whole cut plane. For this purpose conformal mapping and subsequent resummation by means of Padé approximants or Levin transformation are applied.