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Related papers: Nucleon QCD sum rules in instanton medium

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The QCD + QED axial anomaly low-energy theorems are applied to estimate the accuracy of an instanton vacuum - based chiral quark model. The low-energy theorems give an exact relation between the matrix elements of the gluon and photon parts…

High Energy Physics - Phenomenology · Physics 2009-10-30 M. M. Musakhanov , F. C. Khanna

We review our current understanding of instanton effects in the large N_c limit of QCD. We argue that the instanton liquid can have a smooth large N_c limit which is in agreement with scaling relations derived from Feynman diagrams. We also…

High Energy Physics - Phenomenology · Physics 2017-08-23 Thomas Schaefer

The normalization of the gluon condensate and of renormalon-related power corrections in QCD is computed under the assumption that their ``perturbative'' part dominates over any eventual extra contribution from the non-trivial vacuum. The…

High Energy Physics - Phenomenology · Physics 2010-02-03 Georges Grunberg

We calculate the vacuum expectation value of the dimension-5 "mixed" quark-gluon operator, $O_\sigma = \bar\psi (\lambda^a /2) \sigma_{\mu\nu} \psi F_{\mu\nu}^a$, in the instanton vacuum. Within the $1/N_c$--expansion the QCD operator is…

High Energy Physics - Phenomenology · Physics 2009-10-28 M. V. Polyakov , C. Weiss

We examine the radiative $\Delta \to \gamma N$ transition at the real photon point $Q^2=0$ using the framework of light-cone QCD sum rules. In particular, the sum rules for the transition form factors $G_M(0)$ and $R_{EM}$ are determined up…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. Rohrwild

Mass formulas for the light-vector mesons written in terms of the gluon condensate i.e., the trace anomaly in quantum chromodynamics (QCD), are derived on the basis of finite energy QCD sum rules. We utilize sum rules with $s^n$ and…

High Energy Physics - Phenomenology · Physics 2015-06-16 Tomoya Hayata

A new QCD sum rule analysis on the spin-isospin averaged $\rho$, $\omega$ and $\phi$ meson-nucleon scattering lengths is presented. By introducing the constraint relation on the the low energy limit of the vector-current nucleon forward…

Nuclear Theory · Physics 2009-10-30 Yuji Koike , A. Hayashigaki

The light scalar meson nonet above 1 GeV ({\it i.e.\}the $a_{0}$, $K^{\ast}_{0}$ and $f_{0}$) are studied within the framework of QCD sum rules. In conventional QCD sum rules, the calculated masses of this nonet are degenerate, and the mass…

High Energy Physics - Phenomenology · Physics 2009-07-09 J. Zhang , H. Y. Jin , Z. F. Zhang , T. G. Steele , D. H. Lu

We present the first direct calculation on the gravitational form factors (GFFs) of the $N \rightarrow \Delta$ transition using an analytic method, the QCD light-cone sum rules. The matrix element of the quark part of the energy momentum…

High Energy Physics - Phenomenology · Physics 2023-03-22 U. Özdem , K. Azizi

In this paper we show that for a nucleon at rest if the quarks and/or antiquarks are in motion inside the nucleon producing chromo-magnetic field then the mass sum rule in QCD is violated when the confinement potential energy at large…

High Energy Physics - Phenomenology · Physics 2018-04-23 Gouranga C Nayak

The method of QCD sum rules at finite temperature is reviewed, with emphasis on recent results. These include predictions for the survival of charmonium and bottonium states, at and beyond the critical temperature for de-confinement, as…

High Energy Physics - Phenomenology · Physics 2017-01-27 Alejandro Ayala , C. A. Dominguez , M. Loewe

Results for the first test of the ``crude'' QCD continuum model, commonly used in QCD Sum Rule analyses, are presented for baryon correlation functions. The QCD continuum model is found to effectively account for excited state contributions…

Nuclear Theory · Physics 2009-10-28 Derek B. Leinweber

We present a QCD sum-rule determination of the heavy-quark kinetic energy inside a heavy meson, $-\lambda_1/2 m_Q$, which is consistent with the field-theory analog of the virial theorem. We obtain $-\lambda_1\approx (0.10\pm…

High Energy Physics - Phenomenology · Physics 2009-10-28 Matthias Neubert

An introduction to some outstanding issues in QCD is presented, with emphasis on work by Diakonov and co-workers on the influence of the instanton vacuum on low-energy QCD observables. This includes the calculation of input valence-parton…

High Energy Physics - Phenomenology · Physics 2007-05-23 James D. Bjorken

This paper concerns the equilibrium bulk charge and current density correlation functions in quantum media, conductors and dielectrics, fully coupled to the radiation (the retarded regime). A sequence of static and time-dependent sum rules,…

Statistical Mechanics · Physics 2009-11-06 Ladislav Samaj

We calculate the single-particle nucleon characteristics in symmetric nuclear matter with inclusion of the 3N and 4N interactions. We calculated the contribution of the 3N interactions earlier, now we add that of the 4N ones. The…

Nuclear Theory · Physics 2018-03-14 E. G. Drukarev , M. G. Ryskin , V. A. Sadovnikova

With the use of the world-line formalism, the heavy-quark condensate in the SU(N)-QCD is evaluated for the cases when the next-to-1/r term in the quark-antiquark potential at short distances is either quadratic, or linear. In the former…

High Energy Physics - Phenomenology · Physics 2007-05-23 Dmitri Antonov

In this paper we extend our previous work on gluon propagator in the Instanton Liquid Model (ILM) of the QCD vacuum. This objects presents a lot of interest for studies of the heavy quarkonium $Q\bar Q$ observables in the framework of…

High Energy Physics - Phenomenology · Physics 2021-12-13 M. Musakhanov , N. Rakhimov

QCD sum rules for D and B mesons embedded in cold nuclear matter are evaluated. We quantify the mass splitting of D - D-bar and B - B-bar mesons as a function of the nuclear matter density; extrapolated to saturation density it is in the…

Nuclear Theory · Physics 2009-09-29 T. Hilger , R. Thomas , B. Kampfer

Wilson coefficients of light four-quark condensates in QCD sum rules are evaluated for pseudo-scalar $D$ mesons, thus, pushing the sum rules toward mass dimension six. Contrary to the situation for $\bar{q}q$ mesons the impact of the…

Nuclear Theory · Physics 2015-02-02 Thomas Buchheim , Thomas Hilger , Burkhard Kampfer
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