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

摘要

We study the three-body antitriplet B_c → B_nMM' decays with the SU(3) flavor [SU(3)_f] symmetry, where B_c denotes the charmed baryon antitriplet of (Ξ~0_c; ?Ξ~+_c;Λ~+_c), and B_n and M(M') represent baryon and meson octets, respectively. By considering only the S-wave MM'-pair contributions without resonance effects, the decays of B_c → B_nMM' 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 χ~2=d.o.f. = 2.8 for the fit. Consequently, we find that the triangle sum rule of A(Λ~+_c→ nK~0π~+) ? A(Λ~+_c→ pK~?π~+) ? √2A(Λ~+_c→ pK~0π~0) = 0 given by the isospin symmetry holds under SU(3)_f, where A stands for the decay amplitude. In addition, we predict that B(Λ~+_c→ 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 B_c → B_nMM' decays, we compute the branching fractions with the SU(3)_f amplitudes to be compared to the BESIII and LHCb measurements in the future.