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Related papers: Dispersive Methods and QCD Sum Rules for \gamma \g…

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The transition pion-photon form factor is studied within the framework of Light-Cone QCD Sum Rules. The spectral density for the next-to-leading order corrections is calculated for any Gegenbauer harmonic. At the level of the…

High Energy Physics - Phenomenology · Physics 2011-05-13 S. V. Mikhailov , N. G. Stefanis

We calculate the nucleon parameters in nuclear matter using the QCD sum rules method. The radiative corrections to the leading operator product expansion terms are included, with the corrections of the order \alpha_s beyond the logarithmic…

Nuclear Theory · Physics 2009-10-29 E. G. Drukarev , M. G. Ryskin , V. A. Sadovnikova

We study two versions of lightcone sum rules to calculate the $\gamma^*\gamma\rightarrow\pi^0$ transition form factor (TFF) within QCD. While the standard version is based on fixed-order perturbation theory by means of a power-series…

High Energy Physics - Phenomenology · Physics 2022-02-16 Sergey Mikhailov , Alexandr Pimikov , N. G. Stefanis

The existing calculations of the form factors describing the decay $B\to\rho e \nu$ from QCD sum rules have yielded conflicting results at small values of the invariant mass squared of the lepton pair. We demonstrate that the disagreement…

High Energy Physics - Phenomenology · Physics 2011-01-27 Patricia Ball , V. M. Braun

We applied QCD Light Cone Sum Rules to estimate power corrections to the helicity-conserving amplitude in the process $\gamma^*\gamma\to \pi\pi$. We found that above $Q^2 \sim 4$ GeV$^2$ power corrections are numerically small and the…

High Energy Physics - Phenomenology · Physics 2011-09-13 N. Kivel , L. Mankiewicz

A new approach of the QCD sum rule is proposed in which positive and negative-parity baryons couple with each other. With positive and negative-parity states explicitly taken into account, sum rules are derived by means of the dispersion…

High Energy Physics - Phenomenology · Physics 2009-11-11 Yoshihiko Kondo , Osamu Morimatsu , Tetsuo Nishikawa

Sum rules originally derived for the M\"ossbauer Effect are applied to weak semileptonic B decays. The sum rules follow from assuming that the decay by electroweak boson emission of an unstable nucleus or heavy quark in a bound system is…

High Energy Physics - Phenomenology · Physics 2009-10-22 Harry J. Lipkin

Applying the dispersion approach we compute perturbative QCD corrections to the power suppressed soft contribution of $B \to \gamma \ell \nu$ at leading twist. QCD factorization for the $B \to \gamma^{\ast}$ form factors is demonstrated…

High Energy Physics - Phenomenology · Physics 2016-11-03 Yu-Ming Wang

We present the state-of-the-art of the light-cone sum rule approach to Baryon form factors. The essence of this approach is that soft Feynman contributions are calculated in terms of small transverse distance quantities using dispersion…

High Energy Physics - Phenomenology · Physics 2016-08-24 Nils Offen

In this article, we analyze the electromagnetic form factors of the vector heavy-light mesons to the pseudoscalar heavy-light mesons in the framework of three-point QCD sum rules, where the contributions of vacuum condensate terms…

High Energy Physics - Phenomenology · Physics 2024-04-16 Jie Lu , Guo-Liang Yu , Zhi-Gang Wang , Bin Wu

QCD sum rules for the nucleon are considered in complex q^2 plane with inclusion of the radiative corrections of the order alpha_s. It is shown that the radiative corrections affect mainly the residue lambda^2 of the nucleon pole. Their…

High Energy Physics - Phenomenology · Physics 2009-11-11 V. A. Sadovnikova , E. G. Drukarev , M. G. Ryskin

The radiative decays $ B^{*} (D^{*})\to B(D) \gamma$ are investigated in the framework of light cone QCD sum rules. The transition amplitude and decay rates are estimated.It is shown that our results on branching ratios of D meson decays…

High Energy Physics - Phenomenology · Physics 2015-06-25 T. M. Aliev , D. A. Demir , E. Iltan , N. K. Pak

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

Dispersive sum rules constitute long-standing tools for extracting hadron features from QCD. We estimate the systematic uncertainties induced by assuming quark-hadron duality and improve the accuracy of the resulting predictions by…

High Energy Physics - Phenomenology · Physics 2015-03-19 Wolfgang Lucha , Dmitri Melikhov , Silvano Simula

Starting from a bound-state model of weakly bound quarks for ($q \bar{q}$) mesons, we derive a formalism for computing the production or decay of such mesons, whatever the value of their internal orbital angular momentum L. That approach…

High Energy Physics - Phenomenology · Physics 2008-02-03 L. Houra-Yaou , P. Kessler , J. Parisi , F. Murgia , J. Hansson

This talk reviews the recent progress in the extraction of bound-state characteristics from the operator-product expansion (OPE) for field-theory correlators, which constitutes the basis of the method of QCD sum rules. This progress is…

High Energy Physics - Phenomenology · Physics 2012-02-22 Dmitri Melikhov

Dispersion approach based on the constituent quark picture and its applications to weak decays of heavy mesons are reviewed. Meson interaction amplitudes are represented within this approach as relativistic spectral integrals over the mass…

High Energy Physics - Phenomenology · Physics 2012-03-20 Dmitri Melikhov

A model for the description of photonuclear reactions in the multi-GeV range is described that combines the coherent initial state interactions (shadowing) of the incoming photon with an incoherent coupled channel description of final state…

Nuclear Theory · Physics 2007-05-23 Ulrich Mosel

We investigate the hyperon-nucleon interactions in the QCD sum rule starting from the nucleon matrix element of the hyperon correlation function. Through the dispersion relation, the correlation function in the operator product expansion…

Nuclear Theory · Physics 2009-11-10 Yoshihiko Kondo , Osamu Morimatsu

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