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Related papers: Four-Quark Condensates in Nucleon QCD Sum Rules

200 papers

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

The sum rules serve a powerful tool to study the nucleon structure by providing a bridge between the statical properties of the nucleon (such as electrical charge, and magnetic moment) and the dynamical properties (e.g. the transition…

High Energy Physics - Phenomenology · Physics 2010-03-02 M. Gorchtein , D. Drechsel , M. M. Giannini , E. Santopinto

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

Open charm mesons (pseudo-scalar and scalar as well as axial-vector and vector) propagating or resting in nuclear matter display an enhanced sensitivity to the chiral condensate. This offers new prospects to seek for signals of chiral…

Nuclear Theory · Physics 2014-11-20 T. Hilger , R. Schulze , B. Kampfer

With the global color symmetry model being extended to finite chemical potential, we study the density dependence of the local and nonlocal scalar quark condensates in nuclear matter. The calculated results indicate that the quark…

Nuclear Theory · Physics 2009-11-10 Yu-xin Liu , Dong-feng Gao , Hua Guo

QCD sum rules using polynomial kernels are used to evaluate the strong part of the proton-neutron mass difference DeltaM_np in a model independent fashion. The result for the mass difference turns out to depend sensitively on the value of…

High Energy Physics - Phenomenology · Physics 2015-06-05 Nasrallah F. Nasrallah

With the experimental observation of several credible candidates for multiquark hadrons, the latter states re-entered the focus of interest of theoretical strong-interaction physics. Proper treatment of hadronic bound states by quantum…

High Energy Physics - Phenomenology · Physics 2019-08-26 Wolfgang Lucha , Dmitri Melikhov , Hagop Sazdjian

A recent chiral perturbation theory calculation of the in-medium quark condensate $<\bar q q>$ is extended to the isospin-asymmetric case of pure neutron matter. In contrast to the behavior in isospin-symmetric nuclear matter we find only…

Nuclear Theory · Physics 2009-01-16 N. Kaiser , W. Weise

We apply the method of QCD sum rules in the presence of external electromagnetic fields $F_{\mu\nu}$ to the problem of the electromagnetic decays of various vector mesons, such as $\rho\to\pi\gamma$, $K^\ast\to K\gamma$ and…

Nuclear Theory · Physics 2009-10-31 Shi-lin Zhu , W. -Y. P. Hwang , Ze-sen Yang

How fast does the quark condensate in QCD-like theories vary as a function of $N_f$ is inferred from real QCD using chiral perturbation theory at order one-loop. A sum rule is derived for the single relevant chiral coupling-constant, $L_6$.…

High Energy Physics - Phenomenology · Physics 2011-09-13 B. Moussallam

We calculate the mass and residue of the nucleon in nuclear matter in the framework of QCD sum rules using the nucleon's interpolating current with an arbitrary mixing parameter. We evaluate the effects of the nuclear medium on these…

High Energy Physics - Phenomenology · Physics 2015-06-18 K. Azizi , N. Er

Nucleon-nucleon scattering observables are discussed in the context of large Nc QCD. As is well known, the baryon spectrum in the large Nc limit exhibits contracted SU(2Nf) spin-flavor sym- metry. This symmetry can be used to derive…

Nuclear Theory · Physics 2013-01-30 Boris A. Gelman

We compute the density dependence of the quark condensate and how it changes under the influence of isospin-asymmetric nuclear matter. This is achieved by the calculation of the relevant Feynman diagrams using in-medium chiral perturbation…

Nuclear Theory · Physics 2021-08-03 Stephan Hübsch , Daisuke Jido

The properties of dense QCD matter are delineated through the construction of equations of state which should be consistent with the low and high density limits of QCD, nuclear laboratory experiments, and the neutron star observations.…

Nuclear Theory · Physics 2019-12-12 Toru Kojo

The quark-meson coupling model for nuclear matter, which describes nuclear matter as non-overlapping MIT bags bound by the self-consistent exchange of scalar and vector mesons, is modified by introducing medium modification of the bag…

Nuclear Theory · Physics 2008-11-26 Xuemin Jin , B. K. Jennings

Slight sophistications of the QCD sum-rule formalism may have great impact on the reliability of predicted hadron observables, as exemplified for the case of heavy-meson decay constants.

High Energy Physics - Phenomenology · Physics 2012-06-07 Wolfgang Lucha , Dmitri Melikhov , Silvano Simula

In-medium nucleon electromagnetic form factors are calculated in the quark meson coupling model. The form factors are typically found to be suppressed as the density increases. For example, at normal nuclear density and $Q^2 \sim 0.3 {…

Nuclear Theory · Physics 2008-11-26 D. H. Lu , A. W. Thomas , K. Tsushima , A. G. Williams , K. Saito

We explore in more detail the modified quark meson coupling (MQMC) model in nuclear matter. Based on previous studies two different functional forms for the density dependence of the bag constant are discussed. For uniform matter…

Nuclear Theory · Physics 2009-10-30 Horst Mueller , Byron K. Jennings

We use a variational procedure to study finite density QCD in an approximation in which the interaction between quarks is modelled by that induced by instantons. We find that uniform states with conventional chiral symmetry breaking have…

High Energy Physics - Phenomenology · Physics 2009-10-30 M. Alford , K. Rajagopal , F. Wilczek