Related papers: Vector and Axial-Vector correlators in a instanton…
We studied the Adler-Bardeen-Bell-Jackiw anomaly in the context of a finite chiral quark model known as the Spectral Quark Model. Within this model, we obtain the general non-local form of the axial vertex compatible with a non vanishing…
Using experimental spectral data for hadronic tau decays from the OPAL experiment, supplemented by a phenomenologically successful parameterization for the high-s region not covered by the data, we construct a physically constrained model…
Renormalization of the axial vector currents due to Goldstone loops is studied in a simple extension of Manohar - Georgi chiral quark model which incorporates $U(1)_A$ anomaly effects. The polarized strage quark sea in the polarized nucleon…
We compute the Adler function on the lattice from vacuum polarization data with twisted boundary conditions using numerical derivatives. The study is based on CLS ensembles with two flavours of $O(a)$ improved Wilson fermions. We…
We address several aspects of lattice QCD calculations of the hadronic vacuum polarization and the associated Adler function. We implement a representation derived previously which allows one to access these phenomenologically important…
The instanton vacuum provides an effective description of chiral symmetry breaking by local topological fluctuations of the gauge fields, as observed in lattice QCD simulations. The resulting effective dynamics at momenta below $1/\bar\rho…
The hadronic vacuum polarization contribution to the anomalous magnetic moment of a lepton is considered as a function of the lepton mass. We show how the analyticity properties of this function allow for its full reconstruction when it is…
We review the current status of the research on effective nonlocal NJL-like chiral quark models with separable interactions, focusing on the application of this approach to the description of the properties of hadronic and quark matter…
Vector and axial form factors in the quark resonance model are analyzed with a combination of theoretical and phenomenological arguments. The new form of form factors is deduced from $\Delta$(1232) excitation models and available data. The…
We evaluate axial vector transition form factors in holographic QCD models that have been shown to reproduce well recent experimental and theoretical results for the pion transition form factor. Comparing with L3 data on…
The chiral quark model posits pseudoscalar and vector meson couplings to constituent quarks. The parity violating meson-quark couplings lead to anapole moments and form factors of the nucleons. These arise both as parity violating meson…
The influence of the chiral mean field on the kaon dynamics in heavy ion reactions is investigated. Inside the nuclear medium the kaons are described as dressed quasi-particles carrying effective masses and momenta. A momentum dependent…
Wave packet revivals and fractional revivals are hallmark quantum interference phenomena that arise in systems with nonlinear energy spectra, and their signatures in expectation values of observables have been studied extensively in earlier…
The magnetic and quadrupole moments of the vector and axial-vector mesons containing heavy quark are estimated within the light cone sum rules method. Our predictions on magnetic moments for the vector mesons are compared with the results…
We study the vector and axial-vector current correlators in perturbative and non-perturbative regimes of QCD. The correlators in Euclidean coordinate space are calculated on the lattice using the M\"obius domain-wall fermion formulation at…
We derive the the effective lagrangian that describes the interactions among vector, axial-vector mesons and pseudoscalars starting from the extended chiral quark model (ECQM). The results for the low-energy constants of this effective…
We propose a method to expand correlation functions with respect to the spatial components of external momenta. From the coefficients of the expansion it is possible to extract Lorentz-invariant form factors at zero spatial momentum…
The azimuthal correlation between the planes formed by the vectors $(\vec{p}_\ell,\vec{p}_{X_b})$ and $(\vec{p}_\ell,\vec{P}_t)$ in the semileptonic rest frame decay of a polarized top quark $t(\uparrow) \to X_b + l^+ + \nu_\ell$ belongs to…
The properties of the QCD partition function at finite chemical potential are studied within the instanton liquid model. It is shown that the density dependence of the quark-induced instanton-antiinstanton (I-A) interaction leads to the…
The (pion) decays controlled by axial anomaly imply the specific entanglement between photons having also the counterparts for classical electromagnetic waves. This is also a specific case of Eisnstein-Podolsky-Rosen-Bohm-Aharonov effect.…