pNRQCD determination of E1 radiative transitions.

This contribution contains the first numerical computation of the complete set of relativistic corrections of relative order v2 for electric dipole (E1) transitions in heavy quarkonium; in particular, for the processes XbJ(1P) →Υ(1S ) + γ with J = 0; 1; 2. We assume that the momentum transfer of the heavy mesons involved in the reactions lies in the weak-coupling regime of the low-energy effective field theory potential nonrelativistic QCD (pNRQCD) and thus a full perturbative calculation can be performed. [ABSTRACT FROM AUTHOR]