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Related papers: Applying the flow equations to QCD

200 papers

The method of flow equations is applied to QED in the light-front dynamics. To second order in the coupling the particle number conserving part of the effective QED Hamiltonian has two terms of different structure. The first term gives the…

High Energy Physics - Theory · Physics 2007-05-23 E. L. Gubankova

We obtain the binding energy of an infinitely heavy quark-antiquark pair from Dirac brackets by computing the expectation value of the pure QCD Hamiltonian. This procedure exploits the rich structure of the dressing around static fermions.…

High Energy Physics - Theory · Physics 2014-11-18 Patricio Gaete

Starting from the NRQCD Lagrangian the heavy quark-antiquark potential is written in terms of field strength insertions on a static Wilson loop. The relevant matching coefficients are given at the present status of knowledge. The…

High Energy Physics - Phenomenology · Physics 2009-10-31 Nora Brambilla , Antonio Vairo

A brief introduction to the effective Lagrangian treatment of QCD (in the sense of using fields representing physical particles rather than quarks and gluons) will be given. The historical evolution of the subject will be discussed. Some…

High Energy Physics - Phenomenology · Physics 2007-05-23 Joseph Schechter

In this series of lectures, I shall begin with the current investigations on phenomenology of hadron dynamics to demonstrate the importance of solving hadronic bound states within the framework of light-front (LF) QCD. Then, I will describe…

High Energy Physics - Phenomenology · Physics 2007-05-23 Wei-Min Zhang

Based on a previous study of deriving the chiral Lagrangian (CL) from QCD, we illustrate the main feature of QCD predictions for the CL coefficients (CLC) in certain approximations. We first show that, in the large-N(c) limit, the anomaly…

High Energy Physics - Phenomenology · Physics 2014-11-17 qing wang , Yu-Ping Kuang , Hua Yang , Qin Lu

We calculate the coefficients in the chiral Lagrangian approximately from QCD based on a previous study of deriving the chiral Lagrangian from the first principles of QCD in which the chiral Lagrangian coefficients are defined in terms of…

High Energy Physics - Phenomenology · Physics 2009-11-07 Hua Yang , Qing Wang , Yu-Ping Kuang , Qin Lu

We derive the chiral effective Lagrangian for heavy-light mesons in the heavy quark limit from QCD under proper approximations. The low energy constants in the effective Lagrangian are expressed in terms of the light quark self-energy. With…

High Energy Physics - Phenomenology · Physics 2020-09-02 Qing-Sen Chen , Hui-Feng Fu , Yong-Liang Ma , Qing Wang

Using flow equations, we derive an effective quark-quark interaction and obtain the coupled set of gap equations for the condensates of the CFL phase of massless N_f=3 dense QCD. We find two different sources of the infrared cutoff in…

High Energy Physics - Phenomenology · Physics 2017-08-23 E. Gubankova

I consider a model based on a quark--meson interaction Lagrangian. The transition amplitudes are evaluated by computing diagrams in which heavy and light mesons are attached to quark loops. The light chiral symmetry relations and the heavy…

High Energy Physics - Phenomenology · Physics 2014-11-17 Aldo Deandrea

It is argued from geometrical, group-theoretical and physical points of view that in the framework of QCD it is not only necessary but also possible to modify the Dirac equation so that correspondence principle holds valid. The Dirac wave…

High Energy Physics - Theory · Physics 2007-05-23 Ivanhoe Pestov

It is shown how a chiral Lagrangian framework can be used to derive relationships connecting quark-level QCD correlation functions to mesonic-level two-point functions. Crucial ingredients of this connection are scale factor matrices…

High Energy Physics - Phenomenology · Physics 2016-01-12 Amir H. Fariborz , A. Pokraka , T. G. Steele

We address the question of the Lorentz nature of the effective long-range interquark interaction generated by the QCD string with quarks at the ends. Studying the Dyson-Schwinger equation for a heavy-light quark-antiquark system, we…

High Energy Physics - Phenomenology · Physics 2009-11-11 A. V. Nefediev , Yu. A. Simonov

Lecture Notes, Summer School on Effective Theories and Fundamental Interactions, Erice, 1996. The application of effective field theory methods to the low energy structure of QCD is discussed. I emphasize the universal structure of the…

High Energy Physics - Phenomenology · Physics 2007-05-23 H. Leutwyler

The effective quark Lagrangian is written for a light quark in the field of a static antiquark, explicitly containing field correlators as coefficient functions of products of quark operators. At large N_c the closed system of equations for…

High Energy Physics - Phenomenology · Physics 2009-10-31 Yu. A. Simonov , J. A. Tjon

What is the dynamics of heavy quarks and antiquarks in a quark gluon plasma? Can heavy-quark bound states dissociate? Can they (re)combine? These questions are addressed by investigating a Lindblad equation that describes the quantum…

High Energy Physics - Phenomenology · Physics 2017-08-29 Davide De Boni

The quark-antiquark contribution to the BFKL kernel is calculated. Using the effective vertex for the $q\bar q$ pair production in the Reggeon-Reggeon collision we find this contribution by integrating the square of this vertex over…

High Energy Physics - Phenomenology · Physics 2009-10-30 V. S. Fadin , R. Fiore , A. Flachi , M. I. Kotsky

The effective action with homogeneous valence (off-diagonal) gluons as background fields in the extended SU(2) model of QCD is obtained in one-loop approximation. We keep the manifest gauge and Lorentz invariance during whole calculation by…

High Energy Physics - Theory · Physics 2007-05-23 Y. M. Cho , Haewon Lee , D. G. Pak

A rigorous three-dimensional relativistic equation for quark-antiquark bound states at finite temperature is derived from the thermal QCD generating functional which is formulated in the coherent-state representation. The generating…

High Energy Physics - Theory · Physics 2008-11-26 Jun-Chen Su

The effective Hamiltonian, as obtained from applying the Hamiltonian flow equations to front form QED, are solved numerically for positronium. Both the exchange and the annihilation channels are included. The impact of different similarity…

High Energy Physics - Theory · Physics 2007-05-23 Elena Gubankova , Gabor Papp