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Related papers: Instanton vacuum beyond chiral limit

200 papers

The relation between the spectral density of the QCD Dirac operator at nonzero baryon chemical potential and the chiral condensate is investigated. We use the analytical result for the eigenvalue density in the microscopic regime which…

High Energy Physics - Theory · Physics 2009-11-11 J. C. Osborn , K. Splittorff , J. J. M. Verbaarschot

The Cornell potential with the best fitted parameters $\alpha_{s}$ and $\kappa$ are modified by adding terms derived from non-perturbative QCD, which are characterized by a series of non-vanishing vacuum condensates of quarks and gluons. In…

High Energy Physics - Phenomenology · Physics 2008-11-26 Y. B. Ding , X. -H. Guo , X. Q. Li , P. N. Shen

The instanton contribution to the quark distribution functions in the nucleon is estimated. It is shown, that taking into account the instanton induced interaction between quarks allows to explain the anomalous violation of the Ellis-Jaffe…

High Energy Physics - Phenomenology · Physics 2007-05-23 N. I. Kochelev

Spontaneous chiral symmetry breaking in QCD with massless quarks at infinite volume can be seen in a finite box by studying, for instance, the dependence of the chiral condensate from the volume and the quark mass. We perform a feasibility…

High Energy Physics - Lattice · Physics 2010-10-27 Leonardo Giusti , Silvia Necco

Heavy quark effective theory can be used to calculate the values of the semileptonic B^(*) -> D^(*) decays in the limit that the heavy quark masses are infinite. We calculate the lowest order chiral corrections, which are of O(1/M^2), from…

High Energy Physics - Lattice · Physics 2009-11-07 Daniel Arndt

We perform an analysis of the topological and chiral vacuum structure of four-dimensional QCD on the lattice at finite temperature. From correlation functions we show the existence of local correlations between the topological charge…

High Energy Physics - Lattice · Physics 2009-10-30 Markus Feurstein , Harald Markum , Stefan Thurner

We calculate the hadronic matrix elements to $O(p^4)$ in the chiral expansion for the ($\Delta S =1$) $K^0 \to 2 \pi$ decays and the ($\Delta S=2$) $\bar K^0$-$K^0$ oscillation. This is done within the framework of the chiral quark model.…

High Energy Physics - Phenomenology · Physics 2009-10-30 S. Bertolini , J. O. Eeg , M. Fabbrichesi , E. I. Lashin

It is shown in a systematic way that the instanton dilute model can be combined with the global colour symmetry model to form a new nonperturbative QCD model. Based on the quark propagator derived in the instanton dilute liquid…

High Energy Physics - Phenomenology · Physics 2016-08-16 Hongshi Zong , Xiaohua Wu , Xiaofu Lü , Chaohsi Chang , Engang Zhao

We propose to calculate the gluon condensate in lattice QCD in an indirect way by extracting it from the correlator of hadronic currents of heavy quarks. Moments (derivatives with respect to momentum at vanishing momentum) of the vector and…

High Energy Physics - Lattice · Physics 2009-10-28 Alexander Bochkarev

The system of light quark and heavy antiquark source is studied in 1+1 QCD in the large N_C limit. The situation is demonstrated to be the two dimensional analogue of the problem in 3+1 QCD corresponding to the essentially nonlocal case of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Yu. S. Kalashnikova , A. V. Nefediev

The quark gap equation under the rainbow truncation, with two versions of a phenomenological one-gluon exchange interaction and in the presence of a uniform magnetic field is considered. It is argued that in order to describe the quark…

High Energy Physics - Phenomenology · Physics 2013-12-02 Peter Watson , Hugo Reinhardt

The low-energy QCD theorems are generalized in the presence of a constant magnetic field H. Two-loop approximation for the vacuum energy density in the framework of the chiral perturbation theory was obtained and the quark and gluon…

High Energy Physics - Phenomenology · Physics 2009-10-31 N. O. Agasian , I. A. Shushpanov

We discuss direct $CP$ violation in the standard model by giving a new estimate of $\varepsilon'/\varepsilon$ in kaon decays. Our analysis is based on the evaluation of the hadronic matrix elements of the \mbox{$\Delta S =1$} effective…

High Energy Physics - Phenomenology · Physics 2014-11-17 S. Bertolini , J. O. Eeg , M. Fabbrichesi

I explain how instantons break chiral symmetry and how do they bind quarks in baryons. The confining potential is possibly irrelevant for the task.

High Energy Physics - Phenomenology · Physics 2017-08-23 Dmitri Diakonov

The generating functional of heavy baryon chiral perturbation theory at order O(Q^2) in the mean field approximation (with a pseudoscalar source coupling which is consistent with the PCAC-Ward identities on the current quark level) has been…

Nuclear Theory · Physics 2008-02-03 Mariana Kirchbach , Andreas Wirzba

For the one-loop contribution to the QCD vacuum tunneling amplitude by quarks of generic mass value, we make use of a calculational scheme exploiting a large mass expansion together with a small mass expansion. The large mass expansion for…

High Energy Physics - Phenomenology · Physics 2009-10-31 O-Kab Kwon , Choonkyu Lee , Hyunsoo Min

The variational method and the Hamiltonian formalism of QCD are used to derive relativistic, momentum space integral equations for a quark-antiquark system with an arbitrary number of gluons present. As a first step, the resulting infinite…

High Energy Physics - Phenomenology · Physics 2009-10-31 L. Di Leo , J. W. Darewych

The effective quark Lagrangian is derived from the QCD action by means of averaging over the vacuum fields. In the limit of large N_c and keeping for simplicity the lowest order gluonic correlator one obtains nonlinear equations for the…

High Energy Physics - Phenomenology · Physics 2009-10-30 Yu. A. Simonov

Utilizing the in-medium Lorentz decomposition of operators generating QCD condensates we derive general constraints among the latter ones by the requirement of a smooth transition from medium to vacuum. In this way we relate the vacuum…

Nuclear Theory · Physics 2016-04-13 Thomas Buchheim , Burkhard Kampfer , Thomas Hilger

A chiral fermion action allows one to do very clean studies of chiral symmetry breaking in QCD. I will briefly describe how to compute with the overlap action (relatively) cheaply, and then turn to physics: Low modes of the Dirac operator…

High Energy Physics - Lattice · Physics 2007-05-23 Thomas DeGrand