Techniques for computing two-loop QCD corrections to b-->c transitions

Abstract

We have recently presented the complete O(alpha_s^2) corrections to the semileptonic decay width of the b quark at maximal recoil. Here we discuss various technical aspects of that calculation and further applications of similar methods. In particular, we describe an expansion which facilitates the phase space integrations and the treatment of the mixed real-virtual corrections, for which Taylor expansion does not work and the so-called eikonal expansion must be employed. Several terms of the expansion are given for the O(alpha_s^2) QCD corrections to the differential semileptonic decay width of the b --quark at maximal recoil. We also demonstrate how the light quark loop corrections to the top quark decay rate can be obtained using the same methods. We briefly discuss the application of these techniques to the calculation of the O(alpha_s^2) correction to zero recoil sum rules for heavy flavor transitions.

22 pages, revtex

References in corpus (2)

• Two-loop QCD Corrections to $b\to c$ Transitions at Zero Recoil: Analytical Results
• Two-loop QCD corrections to semileptonic b decays at maximal recoil

Cited by in corpus (8)

• Top-Quark Decay at Next-to-Next-to-Leading Order in QCD
• Two-loop QCD corrections to the heavy quark pair production cross section in e+e- annihilation near the threshold
• Two-loop QCD corrections to top quark width
• Non-Abelian Dipole Radiation and the Heavy Quark Expansion
• Two-loop QCD corrections to semileptonic b decays at an intermediate recoil
• Semileptonic decays in the limit of a heavy daughter quark
• Two-loop QCD corrections to semileptonic b-quark decays near maximum recoil
• Isotopic splittings and OPE in B -> D semileptonic decays