We study the semileptonic decays of double heavy baryons using a manifestly Lorentz covariant constituent three-quark model. We present complete results on transition form factors between double-heavy baryons for finite values of the heavy quark/baryon masses and in the heavy quark symmetry limit which is valid at and close to zero recoil. Decay rates are calculated and compared to each other in the full theory, keeping masses finite, and also in the heavy quark limit.
Radiative corrections to the three-body region of the Dalitz plot of baryon semileptonic decays with angular correlation between polarized emitted baryons and charged leptons: The initial-baryon rest frame case
The semileptonic transition of $Λ_b$ baryon is studied using the Hypercentral constituent quark model. The six-dimensional hyperradial $Schr\ddot{o}dinger$ equation is solved in the variational approach to get masses and wavefunctions of heavy baryons. The matrix elements of weak decay are written in terms of the overlap integrals of the baryon wave function. The Isgur-Wise function is determined to calculate exclusive semileptonic decay $Λ_b$ $\rightarrow$ $Λ_c$ $\ell$ $\barν$. The calculated decay rate and the branching ratio of $Λ_b$ baryon are consistent with other theoretical predictions …
The static properties and semileptonic decays of ground-state doubly heavy baryons are studied working in the framework of a non-relativistic quark model. Using a phenomenological potential model, we calculate the ground-state masses and magnetic moments of doubly heavy $ Ω$ and $ Ξ$ baryons. In the heavy quark limit, we introduce a simple form of the universal Isgur-Wise function used as the transition form factor and then investigate the exclusive $ b \rightarrow c $ semileptonic decay widths and branching ratios for $ \frac{1}{2}\rightarrow \frac{1}{2} $ baryon transitions. Our obtained res…
Semileptonic decays of heavy baryons in the relativistic quark model
在重夸克-轻双夸克近似下，研究了由一个重夸克（Q=b，c）和两个轻夸克（q=u，d，s）组成的重子的半轻子衰变.在组分夸克模型中，利用相对论准势方程计算了双夸克和重子的质量和波函数。弱跃迁矩阵元由重子波函数的重叠积分表示。Isgur-Wise函数在整个可达运动学范围内确定。利用重夸克1/mQ展开计算了唯一的半轻子衰变率和不同的不对称性。评估的Lambda_b -> Lambda_c l nu衰变率与其实验值一致。
Relativistic description of semileptonic decays of heavy baryons
在重夸克-轻双夸克近似下，研究了由一个重夸克（Q=b，c）和两个轻夸克（q=u，d，s）组成的重子的半轻子衰变.在组分夸克模型中，用相对论准势方程计算了双夸克和重子的质量和波函数。弱跃迁矩阵元由重子波函数的重叠积分表示。Isgur-Wise函数是在整个可达运动学范围内确定的。用重夸克1/mQ展开计算了唯一的半轻子衰变率。评估的Lambda_b -> Lambda_c l nu衰变率与其实验值一致。
We present a detailed analysis of the heavy-to-light semileptonic decays of the Lambda_b and Lambda_c baryons Lambda_b -> p l- bar(nu)_l and Lambda_c -> n l+ nu_l in the covariant confined quark model. We calculate the invariant and helicity amplitudes of the two processes which are then used to analyze their angular decay distributions, their rates and asymmetry parameters.
Radiative corrections to the three-body region of the Dalitz plot of baryon semileptonic decays with angular correlation between polarized emitted baryons and charged leptons
In the framework of a non-relativistic quark model, the mass spectra of the ground and excited states of doubly heavy $Ξ$ and $Ω$ baryons are calculated. We estimate the mass difference between the $ Ω$ and corresponding $ Ξ$ baryons as $M_Ω-M_Ξ\simeq178 $ MeV for all the states containing $ cc,~bc $, or $ bb $ quarks. A simple form of the universal Isgur-Wise function, as the transition form factor between the doubly heavy baryons, is introduced. Working in the close-to-zero recoil limit, we investigate the $ b \rightarrow c $ semileptonic decay widths and branching fractions of the doubly he…
Precision radiative corrections to the semileptonic Dalitz plot with angular correlation between polarized decaying and emitted baryons: Effects of the four-body region
Precision radiative corrections to the semileptonic Dalitz plot with angular correlation between polarized decaying baryon and emitted charged lepton: Effects of the four-body region
The semileptonic decays of $Λ_{b}\toΛ_{c}^{(*)}\ellν_\ell$ and $Λ_{c}\toΛ^{(*)}\ellν_\ell$ are studied in the light-front quark model in this work. Instead of the quark-diquark approximation, we use the three-body wave functions obtained by baryon spectroscopy. The ground states $(1/2^{+})$, the $λ$-mode orbital excited states $(1/2^{-})$, and the first radial excited states $(1/2^{+})$ of $Λ_{(c)}^{(*)}$ are considered. The discussions are given for the form factors, partial widths, branching fractions, leptonic forward-backward asymmetries, hadron polarizations, lepton polarizations, and the…
Hyperfine mixing in $b\to c$ semileptonic decay of doubly heavy baryons
我们定性地证实了W. Roberts和M. Pervin in Int. J. Mod. Phys. A 24，2401（2009），根据该文献，超精细混合极大地影响了涉及双重重$bc$重子的$b\to c$半轻子衰变的衰变宽度。然而，我们对未混合态的衰变宽度的预测与Roberts和Pervin的工作中报道的结果相差2倍，这种差异转化为混合态。我们进一步表明，重夸克自旋对称性的预测，可能会被用于在未来的实验中提取信息的实际物理$bc$重子的混合物，在一个模型独立的方式。
Numerical precision radiative corrections to the Dalitz plot of light and heavy quark unpolarized baryon semileptonic decays. The cases Xi^0 \to Sigma^+ e \barν and Λ_c^+ \to Λe^+ ν
我们提出并讨论了我们以前的精确结果的数值使用非极化自旋二分之一重子半轻子衰变的辐射校正，这是不妥协的固定形状因子在规定的值。我们提出了各种crosscheriches和其他结果的比较，在文献中的这种分析辐射校正。然而，我们的分析是通用的，适用于重夸克允许的重子的所有电荷分配。该过程以过程^+ e \bar v和Λ_c^+ \to Λe^+ v为例。
Form factors of the weak $Ξ_c \to Ξ(Λ)$ transitions are calculated within the light cone QCD sum rules. The pollutions coming from the contribution of the negative parity $Ξ_c^*$ baryon is eliminated by considering the combinations of sum rules corresponding to the different Lorentz structures. Having obtained the form factors, the branching ratios of the $Ξ_c \to Ξ(Λ) \ell ν$ decays are also calculated, and our predictions are compared with the results of other approaches as well as the measurements done by BELLE and ALICE Collaborations.
A nonrelativistic quark model evaluation of exclusive $b\to c$ semileptonic decay of triply heavy baryons and $c\to s,d$ semileptonic decay of $cb$ baryons
We employ the flavor SU(3) symmetry to analyze semileptonic decays of anti-triplet charmed baryons ($Λ^{+}_{c},Ξ_{c}^{+,0}$) and find that the experimental data on ${\cal B}(Λ_c\toΛ\ell^+ν_{\ell})$ implies $\mathcal{B}(Ξ_c^0\toΞ^-e^+ν_{e})=(4.10\pm0.46)\%$ and $\mathcal{B}(Ξ_c^0\toΞ^-μ^+ν_μ)= (3.98\pm0.57)\%$. When this prediction is confronted with recent experimental results from Belle collaboration $\mathcal{B}(Ξ_c^0\toΞ^-e^+ν_e)=1.31(04\pm07\pm38)\%$ and $\mathcal{B}(Ξ_c^0\toΞ^-μ^+ν_μ)=1.27(06\pm10\pm 37)\%$, it is found that the SU(3) symmetry is severely broken. We then consider the gene…
Precision radiative corrections to the Dalitz plot of baryon semileptonic decays including the spin-momentum correlation of the decaying baryon and the emitted charged lepton
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…
Numerical precision radiative corrections to the Dalitz plot of baryon semileptonic decays including the spin-momentum correlation of the decaying and emitted baryons
