Three-body charmed baryon decays with SU(3) flavor symmetry

We study the three-body antitriplet Bc→BnMM′ decays with the SU(3) flavor [SU(3)f] symmetry, where Bc denotes the charmed baryon antitriplet of (Ξc0,−Ξc+,Λc+), and Bn and M(M′) represent baryon and meson octets, respectively. By considering only the S-wave MM′-pair contributions without resonance effects, the decays of Bc→BnMM′ can be decomposed into irreducible forms with 11 parameters under SU(3)f, which are fitted by the 14 existing data, resulting in a reasonable value of χ2/d.o.f.=2.8 for the fit. Consequently, we find that the triangle sum rule of A(Λc+→nK¯0π+)−A(Λc+→pK−π+)−2A(Λc+→pK¯0π0)=0 given by the isospin symmetry holds under SU(3)f, where A stands for the decay amplitude. In addition, we predict that B(Λc+→nπ+K¯0)=(0.9±0.8)×10−2, which is 3–4 times smaller than the BESIII observation, indicating the existence of the resonant states. For the to-be-observed Bc→BnMM′ decays, we compute the branching fractions with the SU(3)f amplitudes to be compared to the BESIII and LHCb measurements in the future.