Related papers: SU(3) breaking in hyperon transition vector form f…

We perform a new numerical analysis of hyperon semileptonic decays emphasizing the systematic uncertainties. The poor understanding of SU(3) symmetry breaking effects at second order in the vector form factor translates into a large error…

We study the vector and axial vector form factors in the heavy to light transitions in charmed baryon decays using HQET. We calculate the 1/m_c corrections to the form factors and show that these corrections can be significant. We also…

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…

We investigate the semileptonic decay of $\Omega_b\to\Omega_c~{\ell}\bar\nu_{\ell}$ in three lepton channels. To this end, we use QCD sum rule method in three point framework to calculate the form factors defining the matrix elements of…

We use three-flavour hard pion Chiral Perturbation Theory (HPChPT) in both the heavy meson and a relativistic formulation to calculate the chiral logarithms $m^2\log(m^2/\mu^2)$ contributing to the formfactors of the $B_{(s)}\rightarrow…

We calculate hyperon-nucleon and hyperon-hyperon interactions at next-to-leading order in SU(3) baryon chiral perturbation theory extending earlier work by the Bonn-Juelich group. The constructed potentials in momentum space include all…

Light-cone QCD sum rules to leading order in QCD are used to investigate the tensor form factors of the $\Sigma-\Sigma$, $\Xi-\Xi$ and $ \Sigma-\Lambda$ transitions in the range $1 GeV^2 \leq Q^2 \leq 10 GeV^2$. The DAs of $\Sigma$, $\Xi$…

Mesonic fluctuations around the chiral solitons are investigated in the SU(3) chiral quark soliton model. Since the soliton takes the non-hedgehog shape for the hyperons and the hedgehog one for the non-hedgehog baryons in our approach, the…

In this thesis we calculate the baryon axial current within the combined framework of the $1/N_c$ expansion and chiral perturbation theory, where $N_c$ is the number of colors. This calculation shall consider Feynman diagrams to order of…

Baryon Chiral Perturbation Theory (BChPT) combined with the 1/Nc expansion is applied to the SU(3) vector currents. In terms of the xi power counting linking the low energy and 1/Nc expansions according to O(xi) = O(p) = O(1/Nc), the study…

We explore the semileptonic and nonleptonic decays of doubly heavy baryons $(\Omega_{cc}^ {(*) +}, \Omega_{bb}^ {(*)0}, \Omega_{bc}^ {(*) -}, \Omega_{bc}^ {\prime 0}) $ induced by the $s\to u$ transition. Hadronic form factors are…

The decay constants for the $D$ and $D_S$ mesons, denoted $f_D$ and $f_{D_S}$ respectively, are equal in the $SU(3)_V$ limit, as are the hadronic amplitudes for $B_S-\bar B_S$ and $B^0-\bar B^0$ mixing. The leading $SU(3)_V$ violating…

We present a quenched lattice study of the form factors $f_+(q^2)$ and $f_0(q^2)$ of the matrix elements $<\pi | \bar{s} \gamma_\mu u | K >$. We focus on the second-order SU(3)-breaking quantity $[1 - f_+(0)]$, which is necessary to extract…

We calculate the complete $T$ matrices with decuplet contributions for pion-nucleon scattering to order $\mathcal{O}(\epsilon^3)$ in heavy baryon SU(3) chiral perturbation theory. The baryon mass in the chiral limit $M_0$ and the low-energy…

The vector form factor f_+(t) of the semileptonic decay D -> K l nu, measured recently with a high accuracy, can be used to determine the strong coupling constant g_{D_s^* D K}. The latter is related to the normalised coupling \hat{g}…

We calculate the form factors of the $\Lambda_b\to\Lambda_c(2625)$ and $\Xi_b\to\Xi_c(2815)$ transitions, and additionally evaluate the corresponding semileptonic decays and the color-allowed two-body nonleptonic decays. In order to obtain…

Results in the quenched approximation for SU(3) breaking ratios of the heavy-light decay constants and the $\Delta F=2$ mixing matrix elements are reported. Using lattice simulations at $6/g^2=5.7$, 5.85, 6.0, and 6.3, we directly compute…

Model-independent bounds are presented for the form-factors describing the semileptonic decay $\Lambda_b\to\Lambda_ce\bar\nu_e$ at the end-point of the lepton energy spectrum. For the axial-vector form-factor $f_1^A(1)$ we obtain…

Using HISQ $N_f=2+1+1$ MILC ensembles with five different values of the lattice spacing, including four ensembles with physical quark masses, we have performed the most precise computation to date of the $K\to\pi\ell\nu$ vector form factor…

$B_{(s)}$ semi-leptonic decays to the light scalar meson, $B_{(s)}\to S l\bar{\nu}_l, S l \bar{l}\,\,(l=e,\mu,\tau)$, are investigated in the QCD light-cone sum rules (LCSR) with chiral current correlator. Having little knowledge of…