On one master integral for three-loop on-shell HQET propagator diagrams with mass
نویسنده
چکیده
All three-loop on-shell HQET propagator integrals with a loop of a massive quark can be reduced to a set of master integrals, using integration by parts [1]. Some master integrals are known exactly, for other ones a few terms of ε expansions have been calculated [1]. In particular, for the integral I2, the 1/ε and O(1) terms are known. However, in some applications more terms of its ε expansion are needed (A. Czarnecki, A. Pak, work in progress). Here we shall obtain an exact results for I2 and a few additional terms of its expansion in ε.
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تاریخ انتشار 2007