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There exist two distinct ways in realizing the approximate SU(3) flavor symmetry of QCD to describe the two-body nonleptonic decays of charmed baryons: the irreducible SU(3) approach (IRA) and the topological diagram approach (TDA). The TDA has the advantage that it is more intuitive, graphic and easier to implement model calculations. We perform a global fit to the currently available data of two-body charmed baryon decays within the framework of the TDA and IRA. The number of the minimum set of tensor invariants in the IRA and the topological amplitudes in the TDA is the same, namely, five in the tree-induced amplitudes and four in the penguin amplitudes. Since we employ the new LHCb measurements to fix the sign ambiguity of the decay parameters $\beta$ and $\gamma$, the fit results for the magnitudes of $S$- and $P$-wave amplitudes and their phase shift $\delta_P-\delta_S$ in both the TDA and IRA are more trustworthy than our previous analyses with uncertainties substantially improved. These results can be tested in the near future. The perspective of having direct {\it CP} violation in the charmed baryon sector at the per mille level is briefly discussed., Comment: 25 pages, 1 figure

We perform a global fit to the experimental data of two-body charmed baryon decays based on the topological diagrammatic approach (TDA) and take into account the phase shifts between $S$- and $P$-wave amplitudes as inspired by the recent BESIII measurement of the decay asymmetry in the decay $\Lambda_c^+\to \Xi^0K^+$. The TDA has the advantage that it is more intuitive, graphic and easier to implement model calculations. The measured branching fractions and decay asymmetries are well accommodated in the TDA except for a few modes, in particular, the predicted ${\cal B}(\Xi_c^0\to \Xi^-\pi^+)=(2.83\pm0.10)\%$ is larger than its current value. The equivalence of the TDA and the irreducible SU(3) approach (IRA) is established. We show that the number of the minimum set of tensor invariants in the IRA and the topological amplitudes in the TDA is the same and present their relations. The predicted magnitudes of $S$- and $P$-wave amplitudes and their phase shifts are presented for measured and yet-to-be-measured modes in both the TDA and IRA which can be tested in the near future. Besides the decay $\Lambda_c^+\to \Xi^0 K^+$, there exist several modes which proceed only through $W$-exchange. In particular, the observed channel $\Xi_c^0\to \Sigma^+ K^-$ should have phase shifts similar to that in $\Lambda_c^+\to \Xi^0 K^+$ and its decay asymmetry is predicted to be $-0.21\pm0.17$ which can be used to test our theoretical framework. In contrast, the TDA leads to a large $\alpha$ of order $-0.93$ for the decay $\Xi_c^+\to \Xi^0\pi^+$ even after the phase-shift effect is incorporated in the fit., Comment: 24 pages, 1 figure. Tables I, II, V and VI revised, accepted by PRD. arXiv admin note: text overlap with arXiv:2401.15926

Inspired by the recent BESIII measurement of the decay asymmetry and the phase shift between $S$- and $P$-wave amplitudes in the decay $\Lambda_c^+\to \Xi^0K^+$, we perform a global fit to the experimental data of charmed baryon decays based on the topological diagrammatic approach (TDA) which has the advantage that it is more intuitive and easier to implement model calculations. The measured branching fractions and decay asymmetries are well accommodated in TDA except for three modes, in particular, the predicted ${\cal B}(\Xi_c^0\to \Xi^-\pi^+)=(2.83\pm0.10)\%$ is larger than its current value. The predicted magnitudes of $S$- and $P$-wave amplitudes and their phase shifts are presented for measured and yet-measured modes which can be tested in forthcoming experiments., Comment: 5 pages, 1 figure, Tables II-IV revised

In this work, we carry out a global fitting for the two-body weak decays of antitriplet charmed baryons in both SU(3) respected and broken scenarios incorporating all the available data up to date. In the SU(3) irreducible representation approach (IRA), more amplitudes for irreducible representation terms are taken into account and the ranges for their coefficients in each scenarios are predicted. By a comparison among various fitting schemes in this work, experimental data prefer the SU(3) symmetry breaking scenario. Observables of interest, branching fractions and decay asymmetries of all the Cabibbo-favored (CF), singly Cabibbo-suppresed (SCS) and doubly Cabibbo-suppressed (DCS) channels are calculated in the chosen fitting scheme. Most of our predictions are consistent well with experimental data. We further propose more ways to explore the SU(3) symmetry in charmed baryon decays. An improved measurement for $\alpha(\Lambda_c^+\to p K_S)$ is called for since predictions from both fittings, including the one in current work and earlier works, and the pole model calculation prefer an opposite sign from previous experimental value. Given branching fractions of most of the CF modes and part of the SCS modes being measured, predictions for the remaining channels, including the DCS modes as well as more decay asymmetries, are anticipated to be checked by the upcoming experiments in BESIII, Belle/Belle-II and LHCb., Comment: 20 pages, 10 tables; accepted version for JHEP