Some recent results on evaluating Feynman integrals
نویسنده
چکیده
where ki, i = 1, . . . , h, are loop momenta and the denominators Er are either quadratic of linear with respect to ki and external momenta q1, . . . , qN . By default, the integrals are dimensionally regularized with d = 4− 2ǫ. If the number of Feynman integrals needed for a given calculation is small or/and they are simple, one evaluates, by some methods, every scalar Feynman integral of the given family. Various methods are used, in particular, alpha and/or Feynman parameters, Mellin–Barnes (MB) representation [1,2] and differential equations [3]. In the next section, the method of MB representation is briefly reviewed. If it is necessary to evaluate a lot of complicated Feynman integrals (1) the standard way is to apply integration by parts (IBP) [4] relations
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