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In this study, we compute the radiative corrections to the $\Lambda_b \to p$ transition form factors at next-to-leading logarithmic accuracy, employing the framework of QCD light-cone sum rules with the light-cone distribution amplitudes of…

High Energy Physics - Phenomenology · Physics 2026-02-23 Jiang-Lin Zhou , Yong-Kang Huang

Accessing hadronic form factors at large momentum transfers has traditionally presented a challenge for lattice QCD simulations. Here we demonstrate how a novel implementation of the Feynman-Hellmann method can be employed to calculate…

In this work, we study the four form-factors $f_1(Q^2)$, $f_2(Q^2)$, $g_1(Q^2)$ and $g_2(Q^2)$ of the $\Sigma \to n$ in the framework of the light-cone QCD sum rules approach up to twist-6 three valence quark light-cone distribution…

High Energy Physics - Phenomenology · Physics 2007-05-23 Z. G. Wang

Predictions for the electromagnetic form factors of the Lambda$, Sigma and Xi hyperons are presented. The numerical calculations are performed within the framework of the fully relativistic constituent-quark model developed by the Bonn…

Nuclear Theory · Physics 2009-11-10 T. Van Cauteren , D. Merten , T. Corthals , S. Janssen , B. Metsch , H. -R. Petry , J. Ryckebusch

We discuss the nonleading, ``soft" contribution to the pion form factor at intermediate momentum transfer within operator product expansion approach. We argue, that the corresponding contribution can temporarily {\bf simulate} the leading…

High Energy Physics - Phenomenology · Physics 2009-09-25 A. Zhitnitsky

We present an investigation of the pion's electromagnetic form factor F_{\pi}(Q^2) in the spacelike region utilizing two new ingredients: (i) a double-humped, endpoint-suppressed pion distribution amplitude derived before via QCD sum rules…

High Energy Physics - Phenomenology · Physics 2014-11-17 A. P. Bakulev , K. Passek-Kumerički , W. Schroers , N. G. Stefanis

The suggestion of momentum dependence in the amplitude for rho-omega mixing has generated concern over related implications for vector meson dominance and the photon-rho coupling. We discuss two established representations of vector meson…

High Energy Physics - Phenomenology · Physics 2008-11-26 H. B. O'Connell , B. C. Pearce , A. W. Thomas , A. G. Williams

The electromagnetic form factor of the pion in the space-like region, and at finite temperature, $F_{\pi}(Q^{2},T)$, is obtained from a QCD Finite Energy Sum Rule. The form factor decreases with increasing T, and vanishes at some critical…

High Energy Physics - Phenomenology · Physics 2009-10-28 C. A. Dominguez , M. Loewe , J. S. Rozowsky

Electroweak transition form factors of heavy meson decays are important ingredients in the extraction of the Cabibbo-Kobayashi-Maskawa (CKM) matrix elements from experimental data. In this work, within a light-front framework, we calculate…

High Energy Physics - Phenomenology · Physics 2014-11-20 J. P. B. C. de Melo , T. Frederico

We calculate the coupling constants between the light vector mesons and heavy baryons within the framework of the light-cone QCD sum rule in the leading order of heavy quark effective theory. Most resulting sum rules are stable with the…

High Energy Physics - Phenomenology · Physics 2009-11-13 Peng-Zhi Huang , Hua-Xing Chen , Shi-Lin Zhu

We calculate the penguin form factor for the (B -> eta l^+ l^-) decay. This form factor is calculated in light cone QCD sum rules, including contributions from wave functions up to twist-4, as well as mass corrections of the light (eta)…

High Energy Physics - Phenomenology · Physics 2011-09-13 T. M. Aliev , M. Savci

We present an analysis of QCD sum rules for pion form factor in next-to-leading order of perturbation theory for the case of pseudoscalar pion currents. The essential instanton contribution is reanalysed with account for present more…

High Energy Physics - Phenomenology · Physics 2009-11-10 V. V. Braguta , A. I. Onishchenko

The magnetic dipole G_M(Q^2), electric quadrupole G_E(Q^2), and Coulomb quadrupole G_C(Q^2) form factors, describing the spin-3/2 to spin-1/2 electromagnetic transitions, are investigated within the light cone QCD sum rules. The Q^2…

High Energy Physics - Phenomenology · Physics 2015-06-16 T. M. Aliev , Y. Oktem , M. Savci

This talk presents issues pertaining to the quark structure of the pion within QCD, both from the theoretical and from the experimental point of view. We review and discuss the pion-photon transition form factor and the pion's…

High Energy Physics - Phenomenology · Physics 2008-11-07 N. G. Stefanis

The pion form factors of the QCD energy-momentum tensor (EMT) are studied in the instanton liquid model (ILM) of the QCD vacuum. In this approach the breaking of conformal symmetry is encoded in the form of stronger-than-Poisson…

High Energy Physics - Phenomenology · Physics 2024-10-16 Wei-Yang Liu , Edward Shuryak , Christian Weiss , Ismail Zahed

We calculate electromagnetic pion form factors with an analytic model for $\alpha_{\rm s}(Q^2)$ which is infrared (IR) finite without invoking a ``freezing'' hypothesis. We show that for the asymptotic pion distribution amplitude, $F_{\pi…

High Energy Physics - Phenomenology · Physics 2009-10-31 N. G. Stefanis , W. Schroers , H. -Ch. Kim

A pion distribution amplitude, derived from nonlocal QCD sum rules, has been employed to calculate $F_{\gamma^*\gamma\to\pi}(Q^2)$ using light-cone sum rules, and $F_{\pi}(Q^2)$ in NLO QCD perturbation theory. Predictions are presented for…

High Energy Physics - Phenomenology · Physics 2007-05-23 N. G. Stefanis , A. P. Bakulev , S. V. Mikhailov , K. Passek-Kumerički , W. Schroers

In this article, we calculate the electromagnetic form-factor of the $\pi$ meson with the light-cone QCD sum rules. The numerical value $F_\pi^{p}(0) =0.999\pm 0.001$ is in excellent agreement with the experimental data (extrapolated to the…

High Energy Physics - Phenomenology · Physics 2008-12-18 Zhi-Gang Wang , Zhi-Bin Wang

We study photon--meson transition form factors $\gamma^*(Q^2)\gamma \to \pi^0,\eta,\eta'$ at low and moderately high virtualities $Q^2$ of one of the photons, the second photon being real. For the description of the form factor at low…

High Energy Physics - Phenomenology · Physics 2009-10-28 V. V. Anisovich , D. I. Melikhov , V. A. Nikonov

We consider the light-front holographic QCD with the light-front wave functions for mesons, modified for massive quarks. We evaluate the wave functions, distribution amplitudes, and form factors for $\pi$, $\rho$, $K$, and $J/\psi$ mesons…

High Energy Physics - Phenomenology · Physics 2015-10-19 Rohit Swarnkar , Dipankar Chakrabarti