Λb → Λc form factors from QCD light-cone sum rules*

Abstract

In this study, we calculate the transition form factors of decaying into within the framework of light-cone sum rules with the distribution amplitudes (DAs) of the -baryon. In the hadronic representation of the correlation function, we isolate both the and states so that the form factors can be obtained without ambiguity. We investigate the P-type and A-type currents to interpolate light baryons for comparison because the interpolation current for the baryon state is not unique. We also employ three parametrization models for the DAs of in the numerical calculation. We present the numerical predictions for the form factors and branching fractions, averaged forward-backward asymmetry, averaged final hadron polarization, and averaged lepton polarization of the decays, as well as the ratio of the branching ratios . The predicted is consistent with LHCb data.