Related papers: Connections between chiral Lagrangians and QCD sum…
In earlier publications we have analyzed the strong and radiative decays of heavy hadrons in a formalism which incorporates both heavy-quark and chiral symmetries. In particular, we have derived a heavy-hadron chiral Lagrangian whose…
We analyze the recently proposed Spectral Quark Model in the light of Chiral Perturbation Theory in curved space-time. In particular, we calculate the chiral coefficients $L_1, ..., L_{10}$, as well as the coefficients $L_{11}$, $L_{12}$,…
We review the Nambu-Jona-Lasinio (NJL) approach to the dynamical breaking of chiral symmetry in Quantum Chromodynamics (QCD). The subjects treated in Part I include the vacuum structure of QCD, mass spectra and coupling constants of…
We pursue the analysis of a set of generalized DGMLY sum rules for the electromagnetic chiral parameters at order $e^2p^2$ and discuss implications for effective Lagrangians with resonances. We exploit a formalism in which charge spurions…
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…
A chiral invariant Lagrangian describing the tetraquark-quarkonia interaction is considered at the leading and subleading order in the large-$N_{c}$ expansion. Spontaneous chiral symmetry breaking generates mixing of scalar tetraquark and…
Pseudo-scalar and scalar $D$ mesons are considered within the QCD sum rule approach. We present an analysis of the mass splitting of the pseudo-scalar D - D-bar mesons and the relation to QCD condensates. Weinberg type sum rules are derived…
The effective quark Lagrangian is written for a light quark in the field of a static antiquark, explicitly containing field correlators as coefficient functions of products of quark operators. At large N_c the closed system of equations for…
The temperature dependence of quark and gluon condensates in QCD as precursor of the chiral and deconfining phase transition is modelled with a conformally extended non-linear sigma-model including broken chiral and scale invariance. The…
In lattice QCD it is possible, in principle, to determine the parameters in the effective chiral lagrangian (including weak interaction couplings) by performing numerical simulations in the $\epsilon$--regime, i.e. at quark masses where the…
We analytically study two-color QCD with an even number of flavors at high baryon density. This theory is free from the fermion sign problem. Chiral symmetry is broken spontaneously by the diquark condensate. Based on the symmetry breaking…
The QCD sum rule approach is employed in order to study chiral properties of positive- and negative-parity nucleon resonances. It is pointed out that nucleons with an ``exotic'' chiral property, which can be represented by local five-quark…
We develop a scheme for the extraction of the properties of the scalar mesons $f_0(600)$, $f_0(980)$, and $a_0(980)$ from lattice QCD data. This scheme is based on a two-channel chiral unitary approach with fully relativistic propagators in…
We consider the chiral Lagrangian for baryon fields with J^P =\frac{1}{2}^+ or J^P =\frac{3}{2}^+ quantum numbers as constructed from QCD with up, down and strange quarks. The specific class of counter terms that are of chiral order Q^3 and…
A relation among the form factors of $<D \mid A_\mu \mid D^*>$ at $q^2 \to 0$ is derived. It is verified to lowest order in both the $1/m_c$ expansion and the expansion in number of derivatives using the effective lagrangian that…
Commensurate scale relations are perturbative QCD predictions which relate observable to observable at fixed relative scale, such as the ``generalized Crewther relation", which connects the Bjorken and Gross-Llewellyn Smith deep inelastic…
The chiral and heavy quark symmetries of QCD are reviewed. These symmetries are used to predict some low-momentum properties of hadrons containing a single heavy quark. (Lectures given at the CCAST Symposium on Particle Physics at the Fermi…
By incorporating contributions from both the (chromo)electric scale $gT$ and (chromo)magnetic scale $g^2T$, we establish spectral sum rules of quarks for strongly coupled QCD that respect Fermi-Dirac statistics as required by quantum…
We consider the Quasilocal Quark Model of NJL type (QNJLM) as an effective theory of non-perturbative QCD including scalar (S), pseudoscalar (P), vector (V) and axial-vector (A) four-fermion interaction with derivatives. In the presence of…
Spontaneous breaking of chiral symmetry is investigated in the Hamiltonian approach to QCD in Coulomb gauge. The quark wave functional is determined by the variational principle using an ansatz which goes beyond the commonly used BCS-type…