Related papers: Direct Instantons in QCD Nucleon Sum Rules
We introduce a model for nucleons with correlators that include the propagation of pseudo Goldstone bosons as well as the standard correlators for nucleons used in QCD sum rules. From the comparison with experimental nucleon magnetic dipole…
We study instanton effects on inclusive semileptonic $b \rightarrow u$ decay using the heavy quark effective field theory and the operator product expansion. The effect contributes not only to the hadronic matrix element but also to the…
We consider the assumption that a tachyonic gluon mass imitates short-distance nonperturbative physics of QCD. The phenomenological implications include modifications of the QCD sum rules for correlators of currents with various quantum…
The contribution of the anomalous quark-gluon interaction induced by instantons to the polarized and unpolarized gluon distributions in nucleon is estimated. It is shown that this interaction leads to negative gluon polarization in nucleon.
We use QCD sum rules to determine directly the leading-twist non-singlet operator matrix elements based on calculations of three-point correlator functions in configuration space. We find a different result from that obtained by integrating…
We discuss a general diagrammatic description of n-point functions in the QCD instanton vacuum that resums planar diagrams, enforces gauge invariance and spontaneously broken chiral symmetry. We use these diagrammatic rules to derive the…
We pursue the intriguing possibility that larger-size instantons build up diffractive scattering, with the marked instanton-size scale $<\rho> \approx 0.5$ fm being reflected in the conspicuous ``geometrization'' of soft QCD. As an explicit…
Instanton effects can give large contribution to strong interacting processes, especially at the energy scale where perturbative QCD is no longer valid. However instanton contribution to the gluon contribution in constituent quark and…
We propose a new approach to construct QCD sum rules for the pi NN coupling constant, g, starting from the vacuum-to-pion correlation function of the interpolating fields of two nucleons and taking its matrix element with respect to nucleon…
We review the implications of the spontaneous chiral symmetry breaking in QCD for processes involving one, two or more nucleons.
The nuclear density dependencies of the neutron and $\Sigma$ and $\Lambda$ hyperons are important inputs in the determination of the neutron star mass as the appearance of hyperons coming from strong attractions significantly changes the…
Scalar form factor of the nucleon is calculated in the framework of light cone QCD sum rules, using the most general form of the baryon current. Using the result on scalar form factor of the nucleon, the nucleon-scalar "sigma" and "a_0"…
We investigate QCD sum rules for vector currents in the rho meson channel in the nuclear medium. For increased sensitivity, we subtract out the vacuum contributions. With a saturation scheme often considered in the literature, we find these…
Instanton liquid model being effective model of the QCD vacuum describes well the hadrons at low as well at intermediate energies. Thus, contact with perturbative QCD results is possible providing the unique information about the…
Using the light-cone sum rules at leading order, we present an approach to perform the preliminary upper estimation for the nucleon gravitational form factor $D(t)$ ($D$-term contribution). Comparison with the experimental data and with the…
In these lectures we describe the use of Monte Carlo simulations in understanding the role of tunneling events, instantons, in a quantum mechanical toy model. We study, in particular, a variety of methods that have been used in the QCD…
We review various approaches to the calculation of QCD condensates and of the nucleon characteristics in nuclear matter. We show the importance of their self-consistent treatment. The first steps in such treatment appeared to be very…
The in-medium behavior of the nucleon spectral density including self-energies is revisited within the framework of QCD sum rules. Special emphasis is given to the density dependence of four-quark condensates. A complete catalog of…
We perform a semi-classical study of chiral symmetry breaking and of the spectrum of the Dirac operator in QCD with adjoint fermions. For this purpose we calculate matrix elements of the adjoint Dirac operator between instanton zero modes…
Infinite sets of sum rules involving the excitations of infinite nuclear matter are derived using only completeness, the current algebra implicit in QCD, and relativistic covariance. The sum rules can be used for isospin-asymmetric nuclear…