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Measurements and theoretical calculations of meson form factors are essential for our understanding of internal hadron structure and QCD, the dynamics that bind the quarks in hadrons. The pion electromagnetic form factor has been measured…

High Energy Physics - Lattice · Physics 2018-04-18 Jonna Koponen , André Zimermmane-Santos , Christine Davies , G. Peter Lepage , Andrew Lytle

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

The pion and kaon electromagnetic form factors $F_M(Q^2)$ are calculated at the leading order of pQCD using the running coupling constant method. In calculations a dependence of the mesons distribution amplitudes on the hard scale $Q^2$ is…

High Energy Physics - Phenomenology · Physics 2007-05-23 Shahin S. Agaev

QCD sum rules on the light-cone are derived for the sum $f^+ + f^-$ of the $B\to \pi$ and $D\to \pi$ form factors taking into account contributions up to twist four. Combining the results with the corresponding $f^+$ form factors calculated…

High Energy Physics - Phenomenology · Physics 2009-10-31 A. Khodjamirian , R. Rückl , C. W. Winhart

In many years ago, Isgur and Llewellyn Smith addressed that PQCD is inapplicable to exclusive processes, such as the pion form factor.The main problem is that the asymptotic of PQCD is only about one fourth of the experimental value. We…

High Energy Physics - Phenomenology · Physics 2009-08-25 Tsung-Wen yeh

We calculate the form factors for the baryon number violation processes of a heavy-flavor baryon decaying into a pseudoscalar meson and a lepton. In the framework of the Standard Model effective field theory, the leptoquark operators at the…

High Energy Physics - Phenomenology · Physics 2024-05-21 Lei-Yi Li , Cai-Dian Lü , Jin Wang , Yan-Bing Wei

We analyze the pion transition form factor using dispersion theory. We calculate the singly-virtual form factor in the time-like region based on data for the $e^+e^-\to 3\pi$ cross section, generalizing previous studies on…

High Energy Physics - Phenomenology · Physics 2014-12-19 Martin Hoferichter , Bastian Kubis , Stefan Leupold , Franz Niecknig , Sebastian P. Schneider

We complete the set of QCD light-cone sum rules for $B\to \pi\pi$ transition form factors, deriving a new sum rule for the timelike-helicity form factor $F_t$ in terms of dipion distribution amplitudes. This sum rule, in the leading twist-2…

High Energy Physics - Phenomenology · Physics 2017-10-04 Shan Cheng , Alexander Khodjamirian , Javier Virto

In this article, we calculate the scalar form-factor of the proton in the framework of the light-cone QCD sum rules approach with the three valence quark light-cone distribution amplitudes up to twist-6, and observe the scalar form-factor…

High Energy Physics - Phenomenology · Physics 2009-11-11 Zhi-Gang Wang , Shao-Long Wan , Wei-Min Yang

The isovector axial vector form factors of $N \rightarrow \Delta$ transition are calculated by employing Light-cone QCD sum rules. The analytical results are analysed by both the conventional method, and also by a Monte Carlo based approach…

High Energy Physics - Phenomenology · Physics 2016-10-19 A. Kucukarslan , U. Ozdem , A. Ozpineci

We reanalyze the $\gamma\gamma^{*} \to \pi^{0}$ transition form factor $F_{\pi\gamma}(Q^2)$ within the QCD light-cone sum rules method with the twist-4 accuracy. In computations the pion leading twist distribution amplitude (DA) with two…

High Energy Physics - Phenomenology · Physics 2014-11-18 S. S. Agaev

The proton to $\Delta^+$ resonance transitional gravitational form factors are calculated to leading one-loop order using chiral perturbation theory in our recent work [1]. We take into account the leading electromagnetic and strong…

High Energy Physics - Phenomenology · Physics 2025-03-31 Bao-Dong Sun

New, accurate measurements of the pion and kaon electromagnetic form factors are expected in the near future from experiments at electron-positron colliders,using the radiative return method. We construct a model for the timelike pion…

High Energy Physics - Phenomenology · Physics 2015-06-25 Christine Bruch , Alexander Khodjamirian , Johann H. Kuhn

We derive QCD light-cone sum rules for the hadronic matrix elements of the heavy baryon transitions to nucleon. In the correlation functions the $\Lambda_c,\Sigma_c$ and $\Lambda_b$ -baryons are interpolated by three-quark currents and the…

High Energy Physics - Phenomenology · Physics 2015-05-30 A. Khodjamirian , Ch. Klein , Th. Mannel , Y. -M. Wang

I calculate the form factors describing semileptonic and penguin-induced decays of B mesons into light pseudoscalar mesons. The form factors are calculated from QCD sum rules on the light-cone including contributions up to twist 4,…

High Energy Physics - Phenomenology · Physics 2009-10-31 Patricia Ball

The new BABAR data on the pion-photon transition form factor arouses people's new interests on the determination of pion distribution amplitude. To explain the data, we take both the leading valence quark state's and the non-valence quark…

High Energy Physics - Phenomenology · Physics 2015-03-17 Xing-Gang Wu , Tao Huang

In this article, we calculate the vector form factors $f^+_{K\pi}(Q^2)$ and $f^-_{K\pi}(Q^2)$ within the framework of the light-cone QCD sum rules approach. The numerical values of the $f^+_{K\pi}(Q^2)$ are compatible with the existing…

High Energy Physics - Phenomenology · Physics 2008-11-26 Z. G. Wang , S. L. Wan

We have applied the light-front formalism to calculate the electromagnetic form factors for the pion and the kaon from two models at low and high energies in order to explore the differences between such models. We have also compared the…

High Energy Physics - Phenomenology · Physics 2014-11-20 O. A. T. Dias , V. S. Filho , J. P. B. C. de Melo

The recent BaBar measurements of the $\gamma\gamma^{*}\to \pi^{0}$ form factor show spectacular deviation from perturbative QCD computations for large space-like $Q^{2}$. At $34\,\rm GeV^{2}$ the data are more than 50% larger than…

High Energy Physics - Phenomenology · Physics 2011-03-07 T. N. Pham , X. Y. Pham

Recent polarization transfer measurements of the proton electromagnetic form factors yield very different results from previous Rosenbluth extractions. This inconsistency implies uncertainties in our knowledge of the form factors and raises…

Nuclear Experiment · Physics 2009-11-10 J. Arrington
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