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Confining configurations are introduced into the standard instanton vacuum model. This drastically improves theoretical properties of the vacuum: instanton size density $d(\rho)$ stabilizes at $\rho\sim 0.2 fm$, all chiral effects are…

High Energy Physics - Phenomenology · Physics 2009-07-28 Yu. A. Simonov

We study instanton effects in QCD at very high baryon density. In this regime instantons are suppressed by a large power of $(\Lambda_{QCD}/\mu)$, where $\Lambda_{QCD}$ is the QCD scale parameter and $\mu$ is the baryon chemical potential.…

High Energy Physics - Phenomenology · Physics 2009-11-07 Thomas Schaefer

We develop a relativistic quark model for pion structure, which incorporates the non-trivial structure of the vacuum of Quantum Chromodynamics as modelled by instantons. Pions are boundstates of quarks and the strong quark-pion vertex is…

High Energy Physics - Phenomenology · Physics 2009-10-31 I. V. Anikin , A. E. Dorokhov , A. E. Maximov , L. Tomio , V. Vento

Heavy hadrons are analyzed in a random and dilute gas of instantons. We derive the instanton-induced interactions between heavy and light quarks at next to leading order in the heavy quark mass and in the planar approximation, and discuss…

High Energy Physics - Phenomenology · Physics 2009-10-28 S. Chernyshev , M. A. Nowak , I. Zahed

In these notes we describe the basic formulation of the parametrization scheme for the instantaneous nonlocal chiral quark model in the three flavor case. We choose to discuss the Gaussian, Lorentzian-type, Woods-Saxon and sharp cutoff…

High Energy Physics - Phenomenology · Physics 2008-11-26 Hovik Grigorian

The instanton size $\rho$ and inter-instanton distance $R$ are the main parameters of Instanton Liquid Model (ILM) of the QCD vacuum. Various estimates show that $\rho\approx1/3$ fm and $R\approx1$ fm, and the corresponding packing…

High Energy Physics - Phenomenology · Physics 2023-03-07 Mirzayusuf Musakhanov

The correlator of vector and nonsinglet axial-vector currents in the external electromagnetic field is calculated within the instanton liquid model of QCD vacuum. In general the correlator has two Lorentz structures: longitudinal w_L and…

High Energy Physics - Phenomenology · Physics 2009-01-07 A. E. Dorokhov

We look for instanton solutions in a class of two scalar field gravity models, which includes the low energy string action in four dimensions. In models where the matter field has a potential with a false vacuum, we find that non-singular…

High Energy Physics - Theory · Physics 2009-10-31 P. M. Saffin , Anupam Mazumdar , E. J. Copeland

A fundamental question in QCD is the non-perturbative structure of hadrons at the amplitude level--not just the single-particle flavor, momentum, and helicity distributions of the quark constituents, but also the multi-quark, gluonic, and…

High Energy Physics - Phenomenology · Physics 2017-08-23 Stanley J. Brodsky

The transition form factor, decay width and charge form factor of pion are calculated within the model of induced nonlocal quark currents based on the assumption that the nonperturbative QCD vacuum can be characterized by a homogeneous…

High Energy Physics - Phenomenology · Physics 2007-05-23 Ja. V. Burdanov , G. V. Efimov , S. N. Nedelko

We review recent theoretical results from our systematic study of QCD-instanton contributions to eP processes, involving a hard momentum scale Q. The main issues are: the absence of IR divergencies due to a dynamical suppression of…

High Energy Physics - Phenomenology · Physics 2009-10-30 Sven Moch , Andreas Ringwald , Fridger Schrempp

We study light quark interactions in the instanton liquid at finite quark/baryon number density analyzing chiral and diquark condensates and investigate the behaviors of quark dynamical mass and both condensates together with instanton…

High Energy Physics - Lattice · Physics 2009-11-07 S. V. Molodtsov , G. M. Zinovjev

QCD vacuum gluon fields are modelled by hyperspherical domains of constant field strength. The pure glue theory confines static quarks. Solutions of the Dirac operator have chirality properties in agreement with lattice results.

High Energy Physics - Phenomenology · Physics 2017-08-23 A. C. Kalloniatis , S. N. Nedelko

The local structure of low-lying eigenmodes of the overlap Dirac operator is studied. It is found that these modes cannot be described as linear combinations of 't Hooft "would-be" zeromodes associated with instanton excitations that…

High Energy Physics - Lattice · Physics 2007-05-23 I. Horvath , S. J. Dong , T. Draper , F. X. Lee , H. B. Thacker , J. B. Zhang

Starting from the approximate symmetries of QCD, namely chiral symmetry for light quarks and spin and flavor symmetry for heavy quarks, we investigate the low-energy properties of heavy hadrons. For this purpose we construct a consistent…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. Ebert , T. Feldmann

The strangeness content of hadronic matter is studied in a string-flip model that reproduces various aspects of the QCD-inspired phenomenology, such as quark clustering at low density and color deconfinement at high density, while avoiding…

Nuclear Theory · Physics 2009-11-07 G. Toledo Sanchez , J. Piekarewicz

We investigate the contribution that instantons make to the QCD chiral condensate for Nf= 0, 1 and 2 quark flavours. We use a simplified model: the instantons are a (weighted) gas, the fermionic integrations are restricted to the subspace…

High Energy Physics - Phenomenology · Physics 2007-05-23 U. Sharan , M. Teper

The Constituent Quark Model has provided a remarkable description of the experimentally observed hadron spectrum but still has no firm theoretical basis. Attempts to provide a QCD justification discussed at Hadron99 include QCD Sum Rules,…

High Energy Physics - Phenomenology · Physics 2014-11-17 Harry J. Lipkin

The pion form factors of the QCD energy-momentum tensor (EMT) are studied in the instanton liquid model (ILM) of the QCD vacuum. In this approach the breaking of conformal symmetry is encoded in the form of stronger-than-Poisson…

High Energy Physics - Phenomenology · Physics 2024-10-16 Wei-Yang Liu , Edward Shuryak , Christian Weiss , Ismail Zahed

I describe how simulations of lattice QCD using the path integral formulation provide the two basic quantum mechanical properties of QCD, its ground state in which correlation functions are calculated, and Fock state wavefunctions between…

High Energy Physics - Lattice · Physics 2023-01-20 Rajan Gupta