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Related papers: Pion Form Factors in Holographic QCD

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In this article, we calculate the scalar form-factors $f_{\pi\pi}(Q^2)$ and $f_{KK}(Q^2)$ in the framework of the light-cone QCD sum rules approach. The numerical value of the $f_{\pi\pi}(Q^2)$ changes quickly with variation of $Q^2$ near…

High Energy Physics - Phenomenology · Physics 2008-11-26 Zhi-Gang Wang

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

We calculate the pion and kaon electromagnetic form factors in finite volume for a generic momentum transfer in space-like region, using SU(3) chiral perturbation theory. To this end, we first find the hadronic matrix element in a new form…

High Energy Physics - Phenomenology · Physics 2016-04-15 Karim Ghorbani

The pion electromagnetic form factor is calculated at lower and higher momentum transfer in order to explore constituent quark models and the differences among those models. In particular, the light-front constituent quark model is utilized…

High Energy Physics - Phenomenology · Physics 2016-10-19 J. P. B. C. de Melo , Rômulo Moreira Moita , Kazuo Tsushima

We analyze a pion form factor formulation which fulfills the Analyticity requirement within the Hidden Local Symmetry (HLS) Model. We show that it implies an $s$--dependent dressing of the $\rho-\gamma$ VMD coupling and an account of…

Nuclear Theory · Physics 2008-11-26 M. Benayoun , P. David , L. DelBuono , Ph. Leruste , H. B. O'Connell

The pion electromagnetic form factor is calculated with a light-front quark model. The "plus" and "minus" component of the electromagnetic current are used to calculate the electromagnetic form factor in the Breit frame with two models for…

High Energy Physics - Phenomenology · Physics 2009-11-10 J. P. B. C. de Melo

We calculate pion vector and scalar form factors in two-flavor lattice QCD and study the chiral behavior of the vector and scalar radii <r^2>_{V,S}. Numerical simulations are carried out on a 16^3 x 32 lattice at a lattice spacing of 0.12…

High Energy Physics - Lattice · Physics 2012-08-27 JLQCD , TWQCD collaborations , : , S. Aoki , T. W. Chiu , H. Fukaya , S. Hashimoto , T. H. Hsieh , T. Kaneko , H. Matsufuru , J. Noaki , T. Onogi , E. Shintani , N. Yamada

We study phenomenological aspects of the holographic model of chiral symmetry breaking recently introduced by Kuperstein and Sonnenschein (KS). As a first step, we calculate the spectrum of vector and axial-vector mesons in the KS model. We…

High Energy Physics - Theory · Physics 2011-03-28 C. A. Ballon Bayona , Henrique Boschi-Filho , Matthias Ihl , Marcus A. C. Torres

Hadron wave functions and form factors can be extracted using four-point correlators. Stochastic techniques are used to estimate the all to all propagators, which are required for the exact calculation of four-point functions. We apply the…

High Energy Physics - Lattice · Physics 2008-11-26 Constantia Alexandrou , Giannis Koutsou

We study the constraints arising on the expansion parameters c and d of the Pion electromagnetic form factor from the inclusion of pure space-like data and the phase of time-like data along with one space-like datum, using as input the…

High Energy Physics - Phenomenology · Physics 2009-07-22 Gauhar Abbas , B. Ananthanarayan , S. Ramanan

Using holographic models where chiral symmetry is broken through IR b.c.'s, we determine a novel set of relations between QCD matrix elements. In particular, we find that the amplitudes of the three processes pi pi->pi pi, gamma gamma->pi…

High Energy Physics - Phenomenology · Physics 2014-08-25 Pietro Colangelo , Juan Jose Sanz-Cillero , Fen Zuo

The pion electromagnetic form factor is investigated by using the dispersion relation with the superconvergence condition, which was proposed to synthesize the vector meson dominance model and QCD. The absorptive part is given as an…

High Energy Physics - Phenomenology · Physics 2007-05-23 Keiji Watanabe , Hirohisa Ishikawa , Masami Nakagawa

We present detailed numerical results for the pion space-like electromagnetic form factor obtained within a recently proposed model of the pion electromagnetic current in a confining light-front QCD-inspired model. The model incorporates…

High Energy Physics - Phenomenology · Physics 2009-11-10 J. P. B. C. de Melo , T. Frederico , E. Pace , G. Salme

We study a model-independent parameterization of the vector pion form factor that arises from the constraints of analyticity and unitarity. Our description should be suitable up to s^(1/2) ~ 1.2 GeV and allows a model-independent…

High Energy Physics - Phenomenology · Physics 2009-11-07 A. Pich , J. Portoles

We perform a perturbative QCD analysis of the quark transverse momentum effect on the pion-photon transition form factors $F_{\pi \gamma}$ and $F_{\pi \gamma^*}$ in the standard light-cone formalism, with two phenomenological models of…

High Energy Physics - Phenomenology · Physics 2009-10-28 Fu-Guang Cao , Tao Huang , Bo-Qiang Ma

The pion transition form factor $G(q^2)$ is computed on the entire domain of spacelike and timelike momenta using a quantum field theory continuum approach. In analytical continuation of the function $G(Q^2)$ we utilized the Gauge Technique…

High Energy Physics - Phenomenology · Physics 2020-08-05 V. Sauli

We analyze the basic hard exclusive processes: \pi\gamma*\gamma - transition, pion and nucleon electromagnetic form factors, and discuss the analytic continuation of QCD formulas from the spacelike q^2<0 to the timelike region q^2 >0 of the…

High Energy Physics - Phenomenology · Physics 2014-11-17 A. P. Bakulev , A. V. Radyushkin , N. G. Stefanis

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

We use light-cone QCD sum rules to calculate the pion-photon transition form factor, taking into account radiative corrections up to the next-to-next-to-leading order of perturbation theory. We compare the obtained predictions with all…

High Energy Physics - Phenomenology · Physics 2015-05-14 S. V. Mikhailov , N. G. Stefanis

We obtain the electromagnetic form factors of the $\gamma N\Delta$ transition by analyzing recent pion-electroproduction data using a fully relativistic dynamical model. Special care is taken to satisfy Ward-Takahashi identities for the…

Nuclear Theory · Physics 2010-01-18 G. L. Caia , V. Pascalutsa , J. A. Tjon , L. E. Wright