Related papers: Chiral behaviour of Delta B = 2 and Delta C =2 mat…
Theory predictions of heavy-hadron lifetime ratios critically depend on precise determinations of the dimension-six spectator effects arising from the double insertion of the weak effective $|\Delta B| = 1$ Hamiltonian. In the presence of…
We propose a holographic description of heavy-light mesons, i.e. of mesons containing a light and a heavy quark. In the semi-classical string limit, we look at the dynamics of strings tied between two D7 branes. We consider this setup both…
We present preliminary results for the spectrum and decay matrix elements for heavy-light and heavy-heavy mesons, obtained on the 64-node Meiko Computing Surface at the University of Edinburgh. Quark propagators are computed with an…
We study the Delta I =3/2 and Delta S =2 amplitudes for hyperon decays of the form (B to B(prime) pion) at lowest order in chiral perturbation theory. At this order, the Delta I=3/2 amplitudes depend on only one constant. We extract the…
We study the quark mass expansion of the magnetic moments of the nucleon in a chiral effective field theory including nucleons, pions and delta resonances as explicit degrees of freedom. We point out that the usual powercounting applied so…
The extrapolation of the decay amplitudes of the pseudoscalar mesons into two photons from the soft meson limit where it is obtained from the axial-anomaly to the mass shell involves the contribution of the 0^ - continuum. These chiral…
This work evaluates the model dependence of the electric and Coulomb quadrupole amplitudes (E2, C2) in the predominantly M1 (magnetic dipole-quark spin flip) gamma* N -> Delta transition. Both the model-to-model dependence and the intrinsic…
We propose a scheme, based on \Delta(27) flavor symmetry and supplemented by other discrete symmetries and inverse seesaw mechanism, where both the light neutrino masses and the deviation from tri-bimaximal mixing matrix can be linked to…
We present a comprehensive analysis of form factors for two light pseudoscalar mesons induced by scalar, vector, and tensor quark operators. The theoretical framework is based on a combination of unitarized chiral perturbation theory and…
Studying our semirelativistic potential model and the numerical results, which succeeds in predicting and reproducing recently discovered higher resonances of $D$, $D_s$, $B$, and $B_s$, we find a simple expression for the mass gap between…
We study the quark mass expansion of the axial-vector coupling constant g_A of the nucleon. The aim is to explore the feasibility of chiral effective field theory methods for extrapolation of lattice QCD results - so far determined at…
We compute several matrix elements of dimension-six four-fermion operators and extract their B-parameters. The calculations have been performed with the tree-level Clover action at $\beta = 6.0$. The renormalization constants and mixing…
Interactions of $a_2, K^*_2, f_2$ and $f_2'$ tensor-mesons with low-energy $\pi, K, \eta, \eta'$ pseudo-scalar mesons are constrained by chiral symmetry. We derive a chiral Lagrangian of tensor mesons in which the tensor mesons are treated…
We report on our first experiences with a mixed action setup with overlap valence quarks and non-perturbatively O(a) improved Wilson sea quarks. For the latter we employ CLS Nf=2 configurations with light sea quark masses at small lattice…
Consideration of the analytical properties of pion-induced baryon self-energies leads to new functional forms for the extrapolation of light baryon masses. These functional forms reproduce the leading non-analytic behavior of chiral…
We summarize developments concerning the quark mass dependence of nucleon magnetic moments and the axial-vector coupling constant g_A. The aim is to explore the feasibility of chiral effective field theory methods for the extrapolation of…
In a class of beyond-standard-model theories, CP-odd observables, such as the neutron electric dipole moment, receive significant contributions from flavor-neutral P-odd and CP-odd four-quark operators. However, considerable uncertainties…
We study the general dependence of mixing angles on heavy fermion masses when mass hierarchies exist among the fermions. For two generations and small Cabibbo angle, this angle is directly shown to scale like $\mu_1/m_s \pm \mu_2/m_c$,…
I review the status of lattice calculations of heavy-light weak matrix elements, concentrating on semileptonic B decays to light mesons, B -> K* gamma, the B meson decay constant, f_B, and the mixing parameter B_B.
We consider mesons composed of light and heavy quarks and discuss the construction of the corresponding meson wave functions in soft-wall AdS/QCD. We specifically take care that constraints imposed by chiral symmetry breaking and by the…