Related papers: Some implications of meson dominance in weak inter…
By bosonization of an extended NJL model we derive an effective meson theory which describes the interplay between chiral symmetry and heavy quark dynamics. This effective theory is worked out in the low-energy regime using the gradient…
The weak bosons consist of two fermions, bound by a new confining gauge force. The mass scale of this new interaction is determined. At energies below 0.5 TeV the standard electroweak theory is valid. A neutral isoscalar weak boson X must…
Triggered by experimentally driven renewed interest in hyperon properties we address the subject of weak radiative hyperon decays (WRHD). We start with the issue of Hara's theorem and briefly discuss the question of its possible evasion.…
We present a unified description of the vector meson and dilepton production in elementary and in heavy ion reactions. The production of vector mesons ($\rho,\omega$) is described via the excitation of nuclear resonances ($R$). The…
Semileptonic and nonleptonic decays of the B_c meson are studied in the framework of the relativistic quark model. The heavy quark expansion in inverse powers of the heavy (b,c) quark mass is used to simplify calculations while the light…
Dark mesons are bosonic composites of a new, strongly-coupled sector beyond the Standard Model. We consider several dark sectors with fermions that transform under the electroweak group, as arise from a variety of models including…
We study the net dielectron production rates from an ensemble of thermal mesons, using an effective Lagrangian to model their interaction. The coupling between the electromagnetic and the hadronic sectors is done through the vector meson…
We study probe flavor branes supersymmetrically embedded in the Klebanov-Strassler background. The embedding is controlled by a single complex parameter mu related to the quark mass. We study the spectrum of the vector mesons as a function…
I discuss topics in the strong QCD dynamics that are of relevance to studies of the $B$ mesons and to the spectroscopy of heavy hadrons. In particular the limitations from the hadronic dynamics for the determination of the weak-interaction…
The contributions of one-loop diagrams with dynamical vector mesons to masses and decay constants of pseudoscalar mesons are determined. Hereby, a relativistic Lagrangian for both the pseudoscalar-meson octet and the vector-meson nonet is…
We consider a model in which dark matter is a light (350 MeV) Dirac fermion which couples to quarks as an axial-vector current. At center-of-mass (CM) energies below the confinement scale, such a DM interaction structure may be described…
We use recent data on K^+ -> pi^+e^+e^-, together with known values for the pion form factor, to derive the kaon electromagnetic form factor for 0 <q^2 <0.125 (GeV/c)^2. The results are then compared with predictions of the Linear sigma…
The charged Kaon meson ($K^+$) features several hadronic decay modes, but the most relevant contribution to its decay width stems from the leptonic decay $K^+ \rightarrow \mu^+ \nu_\mu $. Given the precision acquired on the rare decay mode…
We introduce the vector meson $\omega$ into the Quark Meson model, and study the impact of vector interactions on the properties of static hadrons using the mean-field approximation. The short-range repulsive force associated with vector…
We analyse the pion electromagnetic, charged-current, and $\pi\gamma$ transition form factors at timelike momentum transfers $q$, $q^2=s\le 1.4$ GeV$^2$, using a dispersion approach. We discuss in detail the propagator matrix of the…
Abelian U(1) gauge group extensions of the Standard Model represent one of the most minimal approaches to solve some of the most urgent particle physics questions and provide a rich phenomenology in various experimental searches. In this…
The weak decay of charmed baryons multiplets into ground state and mesons are investigated using current algebra technique. Some of the interesting results on the partial decays rates and the asymmetry parameters for $\Delta$C=$\Delta$S=-1…
Non-leptonic kaon decays are often described through an effective chiral weak Hamiltonian, whose couplings ("low-energy constants") encode all non-perturbative QCD physics. It has recently been suggested that these low-energy constants…
Dispersion relations---a corollary of unitarity and analyticity---are among the few methods which can be employed to study low energy processes in QCD. In this work we critically revisit the calculation of decay widths of a hypothetical…
The spectra and electroweak decay properties of light mesons are analyzed within the framework of the instantaneous Bethe-Salpeter equation. The interaction kernel comprises alternative spin-structures for a parameterization of confinement…