Useful ratios between two-body nonleptonic and semileptonic decays of B mesons
J. H. Muñoz, N. Quintero
备注:
17 Pages, Version accepted for publication in Rev. Mex. Fis., The title was changed, in section 2 some equations were eliminated, one paragraph was added in section 3, section 5 and the appendix were re-written and section 6 was extended
We compute important ratios between decay widths of some exclusive two-body nonleptonic and semileptonic B decays, which could be test of factorization hy- pothesis. We also present a summary of the expressions of the decay widths and differential decay rates of these decays, at tree level, including l = 0 (ground state), l = 1 (orbitally excited) and n = 2 (radially excited) mesons in the fi- nal state. From a general point of view, we consider eight transitions, namely H \rightarrow P, V, S, A, A, T, P (2S), V (2S). Our analysis is carried out assuming factorization hypothesis and using the WSB, ISGW and CLFA quark models.
Form factors of $D$ decays into $J^{PC}=2^{++}$ tensor mesons are calculated in the light-cone sum rules approach up to twist-4 distribution amplitudes of the tensor meson. The masses of the tensor mesons are comparable to that of the charm quark mass $m_c$; therefore all terms including powers of $m_T/m_c$ are kept out in the expansion of the two-particle distribution amplitude $\langle T|\bar q_{1α}(x) \, q_{2δ}(0)|0\rangle$. Branching ratios of the semileptonic $D \to T\,μ\,\barν_μ$ decays and nonleptonic $D\to T~ P ~(P=K, π)$ decays are taken into consideration. A comparison is also made b…
We calculate the semileptonic and a subclass of sixteen nonleptonic two-body decays of the double charm baryon ground states $Ξ_{cc}^{++},\,Ξ_{cc}^{+}$ and $Ω_{cc}^+$ where we concentrate on the nonleptonic decay modes. We identify those nonleptonic decay channels in which the decay proceeds solely via the factorizing contribution precluding a contamination from $W$-exchange. We use the covariant confined quark model previously developed by us to calculate the various helicity amplitudes which describe the dynamics of the $1/2^+ \to 1/2^+$ and $1/2^+ \to 3/2^+$ transitions induced by the Cabib…
Nonleptonic two-body charmed meson decays in an effective model for their semileptonic decays
我们在一个描述半轻子衰变$D \to V l ν_l$和$D\to P l ν_l$的模型中分析了$D \to P V$、$D \to PP$和$D \to VV$衰变。该模型结合了重夸克有效拉格朗日量和手征微扰理论。我们确定振幅的衰变中的初始$D$介子的直接弱湮灭是不存在或可忽略的,其中的末态相互作用是小的。这种分析减少了模型参数选择的任意性。计算的衰变宽度与实验结果符合得很好。
In this work, the transition form factors are calculated for the semileptonic $D_{(s)} \to A \ell^+ ν$ where $A=a_{1}, b_{1}, K_{1}(1270,1400)$, i.e., $D^{+} \to a^{0}_{1} (b^{0}_{1}, K^{0}_{1}) \ell^+ ν$, $D^{0} \to a^{-}_{1} (b^{-}_{1}) \ell^+ ν$, and $D^{+}_{s}\to K^{0}_{1} \ell^+ ν$ in the frame work of the light-cone QCD sum rules (LCSR) approach up to the twist-3 distribution amplitudes (DAs). Since the masses of these axial vector mesons are comparable to the charm quark mass, we keep out in our calculations all terms including ${m_{A}}/{m_c}$ in expansion of two--parton DAs. Branching …
Exclusive semileptonic and nonleptonic $J/ψ$ decays
Federal Research Center “Computer Science and Control” Russian Academy of Sciences(俄罗斯科学院计算机科学与控制中心);Faculty of Physics, Lomonosov Moscow State University(莫斯科国立大学物理系)
We explore the semileptonic and nonleptonic decays of doubly heavy baryons $(Ω_{cc}^ {(*) +}, Ω_{bb}^ {(*)0}, Ω_{bc}^ {(*) -}, Ω_{bc}^ {\prime 0}) $ induced by the $s\to u$ transition. Hadronic form factors are parametrized by transition matrix elements and are calculated in the light front quark model. With the form factors, we make use of helicity amplitudes and analyze semileptonic and nonleptonic decay modes of doubly heavy baryons. Benchmark results for partial decay widths, branching fractions, forward-backward asymmetries and other phenomenological observables are derived. We find that …
The semileptonic decays and two-body nonleptonic decays of light baryon octet ($T_8$) and decuplet ($T_{10}$) consisting of light $u,d,s$ quarks are studied with the SU(3) flavor symmetry in this work. We obtain the amplitude relations between different decay modes by the SU(3) irreducible representation approach, and then predict relevant branching ratios by present experimental data within $1 σ$ error. We find that the predictions for all branching ratios except $\mathcal{B}(Ξ\rightarrow Λ^0π)$ and $\mathcal{B}(Ξ^*\rightarrow Ξπ)$ are in good agreement with present experimental data, that im…
We study the radiative and weak nonleptonic decays of vector B-mesons within the covariant confined quark model (CCQM) developed in our previous papers. First, we calculate the matrix elements and decays widths of the radiative decays $B^\ast\to Bγ$. The obtained results are compared with those obtained in other approaches. Then we consider the nonleptonic decays $B^\ast\to D^\ast V$ which proceed via tree-level quark diagrams. It is shown that the analytical expressions for the amplitudes correspond to the factorization approach. In the framework of our model we calculate the leptonic decay c…
The semileptonic and nonleptonic decays of the double-beauty axial-vector tetraquark $T_{bb;\overline{u} \overline{d}}^{-}$ to a state $\widetilde{T}_{bc; \overline{u}\overline{d}}^{0}$ (hereafter $T_{bb}^{-}$ and $\widetilde{T} _{bc}^{0}$, respectively) are investigated in the context of the QCD sum rule method. The final-state tetraquark $\widetilde{T}_{bc}^{0}$ is treated as an axial-vector particle built of a heavy axial-vector diquark $ b^{T}γ_{μ}Cc$ and light scalar antidiquark $\overline{u}Cγ_{5} \overline{d}^{T}$. Its spectroscopic parameters are calculated using the two-points sum rul…
Final-State Phases in Doubly-Cabibbo-Suppressed Charmed Meson Nonleptonic Decays
Cabibbo偏爱的非轻子粲粒子衰变在$\bar K π$和$\bar K^* π$通道中表现出大的末态相位差,但在$\bar K ρ$通道中没有。我们很有兴趣知道由$c \to d u \bar s$子过程控制的双Cabibbo抑制衰变的末态相的相应模式。通过测量$D \to K^* π$和$K (ρ, ω,ϕ)$通道的速率,以及确定Dalitz图中频带之间的干扰,概述了用于确定这种相位的实验程序。这样的计划在计划中的高强度粲化粒子源是可行的。
Charm Quark Mass Dependence of QCD Corrections to Nonleptonic Inclusive B Decays
计算了考虑粲夸克质量的非轻子B衰变模$b\rightarrow c\bar u d$的辐射修正。与无质量的情况相比,c夸克质量不为零引起的修正使非轻子率增加(4- 8)%,这取决于重整化点。作为计算的副产品,我们得到了考虑$τ$轻子质量的半轻子衰变$b\rightarrow uτ\barν$辐射修正的解析表达式,并估计了c夸克质量对非轻子衰变模式$b\rightarrow c\bar c s$的影响.
The detection of radially excited heavy meson \\states in recent years and measurement of heavy meson decays, particularly $B_c^+\to J/ψD_s^+$ and $B_c^+\to J/ψD_s^{*+}$, by the LHCb and ATLAS Collaborations, have aroused a lot of theoretical interest in the nonleptonic decays of $b$-flavored mesons. In this paper, we study the exclusive two-body nonleptonic $\bar{B}^0$, $\bar{B_s^0}$, $B^-$ and $B_c^-$-meson decays to two vector meson ($V_1(nS)V_2$) states. Assuming the factorization hypothesis, we calculate the weak-decay form factors from the overlapping integrals of meson wave functions, i…