Related papers: Sum rules for leading vector form factors in hyper…
We investigate the hyperon semileptonic decays within the framework of QCD sum rules. The flavor $ SU(3) $ symmetry breaking effects are analyzed via the relevant form factors and corresponding branching fractions. Employing the $ z…
The derivation of the 1/N_c expansions for the baryon vector and axial-vector currents, in the SU(3) symmetry limit and including perturbative SU(3) breaking, is reviewed. Symmetry breaking effects in the hyperon semileptonic decay form…
Existing analyzes of baryon semileptonic decays indicate the presence of a small SU(3) symmetry breaking in hyperon semileptonic decays, but to provide evidence for SU(3) symmetry breaking, one would need a relation similar to the Gell-Mann…
We present the complete calculation of the SU(3)-breaking corrections to the hyperon vector form factors up to O(p^4) in the Heavy Baryon Chiral Perturbation Theory. Because of the Ademollo-Gatto theorem, at this order the results do not…
QCD sum rules for the determination of form factors of $\Lambda_b$ and $\Lambda_c$ semileptonic decays are investigated. With a form for the baryonic current appropriate for the limits of the heavy quark symmetries, the different tensor…
In this article, the electroweak transition form factors of $\Sigma_b\to\Sigma_c$, $\Xi'_b\to\Xi'_c$ and $\Omega_b\to\Omega_c$ are analyzed within the framework of three-point QCD sum rules. In phenomenological side, all possible couplings…
Flavor SU(3) symmetry breaking in the hyperon semileptonic decay form-factors is analyzed using the 1/N expansion. A detailed comparison with experimental data shows that corrections to f_1 are approximately 10%, which agrees with…
A model-independent determination of the CKM matrix element V_{us} from five measured strangeness-changing hyperon semileptonic decays is performed. Flavor SU(3) symmetry breaking effects in the leading vector and axial-vector form factors…
Existing analyzes of baryon semileptonic decays indicate the presence of a small SU(3) symmetry breaking in hyperon semileptonic decays, but to provide evidence for SU(3) symmetry breaking, one would need a relation similar to the…
We show that the leading $SU(3)$-breaking corrections to the $\Delta S = 1$ $f_1$ vector form factors of hyperons are $O(m_s)$ and $O(m_s^{3/2})$, and are expected to be $\sim 20$--$30\%$ by dimensional analysis. This is consistent with the…
We present a new study of SU(3)-breaking corrections in hyperon vector form factors relevant for the extraction of Vus. A lattice quenched simulation has been performed, showing that it is possible to reach the required precision to extract…
We present a calculation of the SU(3)-breaking corrections to the hyperon transition vector form factors to $\mathcal{O}(p^4)$ in heavy baryon chiral perturbation theory with finite-range regularisation. Both octet and decuplet degrees of…
We investigate the kaon semileptonic decay (K_{l3}) form factors within the framework of the nonlocal chiral quark model from the instanton vacuum, taking into account the effects of flavor SU(3) symmetry breaking. All theoretical…
The octet-baryon axial-vector charges and the g1/f1 ratios measured in the semileptonic hyperon decays are studied up to O(p^3) using the covariant baryon chiral perturbation theory with explicit decuplet contributions. We clarify the role…
We study the semileptonic decay of the doubly heavy baryon $ \Xi^{++}_{cc} $ into the singly heavy baryon $ \Xi^+_{c}$ within the three-point QCD sum rule approach in two possible lepton channels. Our analysis includes perturbative as well…
The baryon vector current is computed at one-loop order in large-Nc baryon chiral perturbation theory, where Nc is the number of colors. Loop graphs with octet and decuplet intermediate states are systematically incorporated into the…
We present the first result for the hyperon vector form factor f_1 for Xi^0 -> Sigma^+ l bar{nu} and Sigma^- -> n l bar{nu} semileptonic decays from fully dynamical lattice QCD. The calculations are carried out with gauge configurations…
We present a quenched lattice calculation of all six form factors: vector [f_1(q^2)], weak magnetism [f_2(q^2)], induced scalar [f_3(q^2)], axial-vector [g_1(q^2)], weak electricity [g_2(q^2)] and induce pseudoscalar [g_3(q^2)] form factors…
The $b \to c$ semileptonic sum rules provide relations between the decay rates of $B \to D^{(*)} \tau\bar\nu$ and $\Lambda_b \to \Lambda_c \tau\bar\nu$. Starting from the heavy quark and zero-recoil limits, we revisit the derivation of the…
We consider the predictions of chiral perturbation theory for $SU(3)$ breaking in the axial vector form factor $g_1$ measured in semileptonic hyperon decays. We confirm that if only octet baryon intermediate states are included, the…