Two-body charmed baryon decays involving decuplet baryon in the quark-diagram scheme

In the quark-diagram scheme, we study the charmed baryon decays of $$\mathbf{B}_c\rightarrow \mathbf{B}^* M$$ B c → B ∗ M , where $$\mathbf{B}_c$$ B c is $$\Lambda _c^+$$ Λ c + or $$\Xi _c^{+(0)}$$ Ξ c + ( 0 ) , together with $$\mathbf{B}^*$$ B ∗ (M) the decuplet baryon (pseudoscalar meson). It is found that only two W-exchange processes are allowed to contribute to $$\mathbf{B}_c\rightarrow \mathbf{B}^* M$$ B c → B ∗ M . Particularly, we predict $${\mathcal {B}}(\Lambda _c^+ \rightarrow \Sigma ^{*0(+)} \pi ^{+(0)})=(2.8\pm 0.4)\times 10^{-3}$$ B ( Λ c + → Σ ∗ 0 ( + ) π + ( 0 ) ) = ( 2.8 ± 0.4 ) × 10 - 3 , which respects the isospin symmetry. Besides, we take into account the SU(3) flavor symmetry breaking, in order to explain the observation of $${\mathcal {B}}(\Lambda _c^+\rightarrow \Sigma ^{*+}\eta )$$ B ( Λ c + → Σ ∗ + η ) . For the decays involving $$\Delta ^{++}(uuu)$$ Δ + + ( u u u ) , we predict $${\mathcal {B}}(\Lambda _c^+\rightarrow \Delta ^{++} \pi ^-,\Xi _c^+ \rightarrow \Delta ^{++} K^-) =(7.0\pm 1.4,13.5\pm 2.7)\times 10^{-4}$$ B ( Λ c + → Δ + + π - , Ξ c + → Δ + + K - ) = ( 7.0 ± 1.4 , 13.5 ± 2.7 ) × 10 - 4 as the largest branching fractions in the singly Cabibbo-suppressed $$\Lambda _c^+,\Xi _c^+\rightarrow \mathbf{B}^*M$$ Λ c + , Ξ c + → B ∗ M decay channels, respectively, which are accessible to the LHCb, BELLEII and BESIII experiments.

Final State Interaction Effects on theB+→J/ψρ+Decay

The exclusive decay ofB+→J/ψρ+is studied in the framework of the QCD factorization (QCDF) method and final state interaction (FSI). A directB+→J/ψρ+decay is only occurred via a tree and a penguin based on the quark diagram analysis. The result that is found by using the QCDF method is less than the experimental result, so, the role of FSI is considered. The intermediate statesD+D̅0,D+*D̅0*,D+*D̅0, andD+D̅0*via the exchange ofD-andD-*are contributed to theB+→J/ψρ+decay. The above intermediate states is calculated by using the QCDF method. In the FSI effects the results of our calculations depend on “η” as the phenomenological parameter. The range of this parameter are selected from 1 to 2. For the exchanged particlesD-andD-*, it is found that ifη=1.58~1.83is selected the numbers of the branching ratio are placed in the experimental range. The experimental branching ratio ofB+→J/ψρ+decay is(5±0.8)×10-5, and our prediction number is(1.42±0.36)×10-5in the absence of FSI effects, and it becomes(4.2~5.8)×10-5when FSI contributions are taken into account.

GENERALIZED ANALYSIS ON B → K*ρ WITHIN AND BEYOND THE STANDARD MODEL

We study B → K*ρ modes that are analogues of the much studied B → Kπ modes with B decaying to two vector mesons instead of pseudoscalar mesons, using topological amplitudes in the quark diagram approach. All the theoretical parameters (except for the weak phase γ), such as the magnitudes of the topological amplitudes and their strong phases, can be determined in terms of the observables without any model-dependent assumption. We demonstrate how B → K*ρ can also be used to verify if there exist any relations between theoretical parameters, such as the hierarchy relations between the topological amplitudes and possible relations between the strong phases. Conversely, if there exist reliable theoretical estimates of amplitudes and strong phases, the presence of New Physics could be probed. We show that if the tree and color-suppressed tree are related to the electroweak penguins and color-suppressed electroweak penguins, it is not only possible to verify the validity of such relations but also to have a clean measurement of New Physics parameters. We also present a numerical study to examine which of the observables are more sensitive to New Physics.

BEAUTY-CONSERVING STRANGENESS-CHANGING TWO-BODY HADRONIC DECAYS OF BEAUTY BARYONS

The beauty-conserving strangeness-changing two-body hadronic decays of beauty baryons are examined. Unlike in charm sector where the heavy flavor conserving but strangeness-changing decays are Cabibbo suppressed, in the b-sector they are CKM allowed. The numerical estimates for decay widths of some of the modes are presented in current algebra approach, factorization and quark diagram approach.