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Related papers: Nucleon QCD sum rules in instanton medium

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The QCD sum rules for spin-dependent nucleon-nucleon interactions are formulated and their physical implications are studied. The basic object of the study is the correlation function of the nucleon interpolating field, where the matrix…

Nuclear Theory · Physics 2009-10-31 Y. Kondo , O. Morimatsu

We apply QCD Finite Energy Sum Rules to the scalar-isoscalar current to determine the lightest $u \bar{u} + d \bar{d}$ meson in this channel. We use `pinch-weights' to improve the reliability of the QCD predictions and reduce the…

High Energy Physics - Phenomenology · Physics 2016-09-06 S. N. Cherry , M. R. Pennington

Extending previous work we study the constraints of QCD sum rules on mass and width of light vector and axial-vector mesons in vacuum and in a medium with finite nuclear density. For the latter case especially the effect of nuclear pions…

Nuclear Theory · Physics 2009-11-07 Stefan Leupold

Using the framework of QCD sum rules we predict the twist-3 contribution to the second moment of the polarized nucleon structure function $g_2(x)$. As the relevant local operator depends explicitely on the gluon field, we employ a recently…

High Energy Physics - Phenomenology · Physics 2011-08-11 E. Stein , P. Gornicki , L. Mankiewicz , A. Schaefer , W. Greiner

We calculate the nucleon parameters in nuclear matter using the QCD sum rules approach in Fermi gas approximation. Terms up to 1/q^2 in the operator product expansion (OPE) are taken into account. The higher moments of the nucleon structure…

Nuclear Theory · Physics 2009-11-10 E. G. Drukarev , M. G. Ryskin , V. A. Sadovnikova , Th. Gutsche , Amand Faessler

We analyze the singlet axial form factor of the proton for small momentum transferred in the framework of QCD sum rules using the interpolating nucleon current which explicitly accounts for the gluonic degrees of freedom. As a result we…

High Energy Physics - Phenomenology · Physics 2008-02-03 A. V. Belitsky , O. V. Teryaev

The external-field QCD Sum Rules method is used to evaluate the coupling constant of the light isoscalar-scalar meson (``$\sigma$'' or \epsilon) to the nucleon. The contributions that come from the excited nucleon states and the response of…

Nuclear Theory · Physics 2008-11-26 G. Erkol , Th. A. Rijken , R. G. E. Timmermans

The influence of nonperturbative fields on instantons in quantum chromodynamics is studied. Effective action for instanton is derived in bilocal approximation and it is demonstrated that stochastic background gluon fields are responsible…

High Energy Physics - Phenomenology · Physics 2007-05-23 N. O. Agasian , S. M. Fedorov

QCD sum rules are used to calculate the $q^2$ dependence of the $\pi NN$ coupling $g_{\pi NN} (q^2)$ in the spacelike region $0.5 \ {\mbox{GeV}}^2 \lesssim q^2 \lesssim 1.5\ {\mbox{GeV}}^2$. We study the Borel sum rule for the three point…

Nuclear Theory · Physics 2008-11-26 Thomas Meissner

The nucleon electromagnetic form factors are calculated in light cone QCD sum rules framework using the most general form of the nucleon interpolating current. Using two forms of the distribution amplitudes (DA's), predictions for the form…

High Energy Physics - Phenomenology · Physics 2008-11-26 T. M. Aliev , K. Azizi , A. Ozpineci , M. Savci

We investigate the masses of the lowest c\bar{c} states, the J/psi and eta_c, in nuclear matter using QCD sum rules. Up to dimension four, the differences between the operator product expansions in vacuum and in medium arise from the…

Nuclear Theory · Physics 2011-09-29 Frank Klingl , Sungsik Kim , Su Houng Lee , Philippe Morath , Wolfram Weise

An introduction to the method of QCD sum rules is given for those who want to learn how to use this method. Furthermore, we discuss various applications of sum rules, from the determination of quark masses to the calculation of hadronic…

High Energy Physics - Phenomenology · Physics 2016-11-23 Pietro Colangelo , Alexander Khodjamirian

A recently proposed scheme is used to saturate the spectral side of the QCD sum rules derived from the thermal, two-point correlation functions of the vector and the axial-vector currents. At low temperature, it constructs the spectral…

High Energy Physics - Phenomenology · Physics 2009-11-07 S. Mallik , Sourav Sarkar

The precise quark mass dependence of the one-loop effective action in an instanton background has recently been computed [arXiv:hep-th/0410190]. The result interpolates smoothly between the previously known extreme small and large mass…

High Energy Physics - Theory · Physics 2009-11-11 Gerald V. Dunne , Jin Hur , Choonkyu Lee , Hyunsoo Min

We deduce momentum sum rules for the parton structure functions of a photon target. Non-perturbative QCD contribution to the momentum sum rules follows from conservation of the energy--momentum tensor and it is calculated through the…

High Energy Physics - Phenomenology · Physics 2007-05-23 L. L. Frankfurt , E. G. Gurvich

The pion-baryon sigma terms and the strange-quark condensates of the octet and the decuplet baryons are calculated by employing the method of quantum chromodynamics (QCD) sum rules. We evaluate the vacuum-to-vacuum transition matrix…

High Energy Physics - Phenomenology · Physics 2010-04-21 G. Erkol , M. Oka , G. Turan

The short-time regime of QCD two-point correlation functions is examined through a QCD-Sum-Rule-inspired continuum model. QCD Sum Rule techniques are tested and alternate nucleon interpolating fields are discussed. The techniques presented…

High Energy Physics - Lattice · Physics 2009-10-22 Derek B. Leinweber

We calculate the electromagnetic and the axial form factors of the nucleon within the framework of light cone sum rules (LCSR) to leading order in QCD and including higher twist corrections. In particular we motivate a certain choice for…

High Energy Physics - Phenomenology · Physics 2009-11-11 V. M. Braun , A. Lenz , M. Wittmann

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

The nucleon's tensor charges (isovector $g^v_T={\delta}u-{\delta}d$ and isoscalar $g^s_T={\delta}u+{\delta}d$) are calculated using the QCD sum rules in the presence of an external tensor field. In addition to the standard quark and gluon…

High Energy Physics - Phenomenology · Physics 2009-10-28 Hanxin He , Xiangdong Ji