2026/07/18 by Guo-Liang Yu, Zhi-Gang Wang, Jie Lu +3
#hep-ph
In the framework of QCD sum rules, we systematically analyze the weak transition process B_Q1Q2((1)/(2)+)\rightarrowB_Q1*((3)/(2)+). When doing the operator product expansion in the QCD side, we consider the contributions of perturbative part and vacuum condensate terms up to dimension 6. In the phenomenological side, we eliminate the interferences of the low spin states and negative parity states by employing 16 different dirac structures. As an application, these form factors are finally used to analyze the semileptonic decays of B_Q1Q2((1)/(2)+)\rightarrowB_Q1*((3)/(2)+)lν, where these decays are driven by the transition processes c→ d/s+l++νl and b→ u+l-+νl. The predicted physical quantities include not only the partial widths, ratios of ΓL/ΓT and the branching fractions, but also some observables such as the forward-backward asymmetry parameter AFBl of lepton, the PzF component of the polarization vector for daughter baryon and the longitudinal polarization of the lepton Pzl. We hope all of these theoretical predictions about the weak decays will be helpful for studying the properties of doubly heavy baryons in experiments in the future.