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The DDrho form factor is evaluated in a QCD sum rule calculation for both D and rho off-shell mesons. We study the double Borel sum rule for the three point function of two pseudoscalar and one vector meson currents. We find that the…

High Energy Physics - Phenomenology · Physics 2009-11-07 M. E. Bracco , M. Chiapparini , A. Lozea , F. S. Navarra , M. Nielsen

We present an extension of the QCD sum rule method in the external fields so as to determine the induced pseudoscalar coupling constant g_P, which tests the validity of the partially conserved axial current (PCAC) hypothesis. This is…

Nuclear Theory · Physics 2010-04-19 E. M. Henley , W-Y. P. Hwang , L. S. Kisslinger

We investigate QCD sum rules for vector currents in the rho meson channel in the nuclear medium. For increased sensitivity, we subtract out the vacuum contributions. With a saturation scheme often considered in the literature, we find these…

High Energy Physics - Phenomenology · Physics 2009-11-07 S. Mallik , Andreas Nyffeler

Global fits to the shape of the first QCD Laplace sum rule exhibiting sensitivity to pion-resonance [$\Pi (1300)$] parameters are performed, leading to predictions for the pion-resonance mass and decay constant. Two scenarios are considered…

High Energy Physics - Phenomenology · Physics 2009-10-30 T. G. Steele , J. C. Breckenridge , M. Benmerrouche , V. Elias , A. H. Fariborz

We describe the present status of the pion distribution amplitude as it originated from two sources: (i) a nonperturbative approach, based on QCD sum rules with nonlocal condensates and (ii) a NLO QCD analysis of the CLEO data on…

High Energy Physics - Phenomenology · Physics 2015-06-25 A. P. Bakulev , A. V. Pimikov

We develop a QCD sum rule analysis of the form factor $F_{\gamma^*\gamma^*\pi^0}(q^2,Q^2)$ in the region where virtuality of one of the spacelike photons is small $q^2 \ll 1 GeV^2$ while another is large: $Q^2 \gapprox 1 GeV^2$. We…

High Energy Physics - Phenomenology · Physics 2009-10-28 A. V. Radyushkin , R. T. Ruskov

The procedure of extracting the ground-state parameters from vacuum-to-vacuum and vacuum-to-hadron correlators within the method of sum rules is considered. The emphasis is laid on the crucial ingredient of this method - the effective…

High Energy Physics - Phenomenology · Physics 2014-11-20 Wolfgang Lucha , Dmitri Melikhov , Silvano Simula

In my talk I discuss the theoretical and experimental status of the pion distribution amplitude (DA). I show that the QCD sum rule method with nonlocal condensates (NLC) for the pion DA gives us admissible sets (bunches) of DAs for each…

High Energy Physics - Phenomenology · Physics 2007-05-23 Alexander P. Bakulev

Pion structure functions are considered in the framework of QCD sum rules at the next to leading order. The 2-loop diargam, representing the gluon exchange between the struck quark and spectator, is calculated for space-like pion momentum…

High Energy Physics - Phenomenology · Physics 2007-05-23 K. N. Zyablyuk

We propose a five-dimensional framework for modeling low-energy properties of QCD. In the simplest three parameter model we compute masses, decay rates and couplings of the lightest mesons. The model fits experimental data to within 10%.…

High Energy Physics - Phenomenology · Physics 2008-11-26 Joshua Erlich , Emanuel Katz , Dam T. Son , Mikhail A. Stephanov

We use the transfer matrix formalism to derive non-perturbative sum rules in Wilson's lattice QCD with N_f flavours of quarks. The discretization errors on these identities are treated in detail. As an application, it is shown how the sum…

High Energy Physics - Lattice · Physics 2008-11-26 Harvey B. Meyer

The earlier introduced method of calculation of quark distributions in hadrons, based on QCD sum rules, is improved. The imaginary part of the virtual photon forward scattering amplitude on some hadronic current is considered in the case,…

High Energy Physics - Phenomenology · Physics 2011-09-13 B. L. Ioffe , A. G. Oganesian

We shortly review some applications of the (inverse) Laplace (LSR) transform sum rules in Quantum ChromoDynamics (QCD) for extracting the fundamental QCD parameters (coupling constant $\alpha_s$, quark and gluon condensates) and the hadron…

High Energy Physics - Phenomenology · Physics 2023-09-04 Stephan Narison

Recently the simulation of quantum field theories using man-made physical systems has become realistic. In this publication we present numerical results which support the use of quantum simulation experiments to study quantum field theories…

High Energy Physics - Lattice · Physics 2016-11-03 Wynne Evans , Urs Gerber , Uwe-Jens Wiese

We evaluate the $\pi N$ coupling constant using a QCD sum rule based on the pion-to-vacuum matrix element of the correlator of two interpolating nucleon fields. The part of the correlator with Dirac structure $k\llap/\gamma_5$ is used,…

High Energy Physics - Phenomenology · Physics 2009-10-28 Michael C. Birse , Boris Krippa

With QCD sum rule evaluations, spectral changes of hadrons inside nuclear matter are considered, which shed light on QCD condensates and thus on the non-perturbative structure of the QCD ground state. For some light quark configurations,…

High Energy Physics - Phenomenology · Physics 2007-05-23 R. Thomas , S. Zschocke , T. Hilger , B. Kampfer

We investigate quarkonium mass spectra in external constant magnetic fields by using QCD sum rules. We first discuss a general framework of QCD sum rules necessary for properly extracting meson spectra from current correlators computed in…

High Energy Physics - Phenomenology · Physics 2015-02-25 Sungtae Cho , Koichi Hattori , Su Houng Lee , Kenji Morita , Sho Ozaki

The QCD sum rule approach to the in-medium behavior of hadrons is discussed for omega meson, nucleon and D meson. Emphasis is devoted to the impact of four-quark condensates and to order parameters of spontaneous symmetry breaking.

High Energy Physics - Phenomenology · Physics 2008-11-26 R. Thomas , T. Hilger , B. Kampfer

We consider a simple model of large-Nc QCD defined by a spectrum consisting of an infinite set of equally spaced zero-width vector resonances. This model is an excellent theoretical laboratory for investigating certain approximation schemes…

High Energy Physics - Phenomenology · Physics 2009-11-07 M. Golterman , S. Peris , B. Phily , E. de Rafael

We consider the problem of an harmonic oscillator coupled to a scalar field in the framework of recently introduced dressed coordinates. We compute all the probabilities associated with the decay process of an excited level of the…

Atomic Physics · Physics 2011-08-04 R. Casana , G. Flores-Hidalgo , B. M. Pimentel