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Effect of m_c on b quark chromomagnetic interaction and on-shell two-loop integrals with two masses

A. I. Davydychev·A. G. Grozin
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Abstract

The effect of non-zero c quark mass on b quark HQET Lagrangian, up to 1/m_b level, is calculated at two loops. The results are expressed in terms of dilogarithmic functions of m_c/m_b. This calculation involves on-shell two-loop propagator-type diagrams with two different masses, m_b and m_c. A general algorithm for reducing such Feynman integrals to the basis of two nontrivial and two trivial integrals is constructed.

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A. I. Davydychev, A. G. Grozin. 1998-11-22. Effect of m_c on b quark chromomagnetic interaction and on-shell two-loop integrals with two masses. https://doi.org/10.1103/physrevd.59.054023

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