Three-loop HQET vertex diagrams forB0–B̄0mixing

Three-loop HQET vertex diagrams for B–B̄ mixing

HQET quark - gluon vertex at one loop

We calculate the HQET quark-gluon vertex at one loop, for arbitrary external momenta, in an arbitrary covariant gauge and space-time dimension. Relevant results and algorithms for the three-point HQET integrals are presented. We also show how one can obtain the HQET limit directly from QCD results for the quarkgluon vertex. On leave from Institute for Nuclear Physics, Moscow State University, 1...

Three-loop results in HQET

Two-loop HQET propagator diagrams were reduced [1] to two master integrals, using integration by parts [2] identities. There are 10 generic topologies of three-loop HQET propagator diagrams (Fig. 1). They can be reduced [3], using integration by parts relations, to 8 master integrals (Fig. 2). The algorithm has been constructed by hand, and implemented as a REDUCE package Grinder [3]. It is ana...

Three-Loop Chromomagnetic Interaction in HQET

We compute the three-loop QCD corrections to the quark chromomagnetic moment and thus obtain the matching coefficient and the anomalous dimension of the chromomagnetic interaction in HQET. As a byproduct we obtain the three-loop corrections to the quark anomalous magnetic moment.

On one master integral for three-loop on-shell HQET propagator diagrams with mass

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...