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Related papers: Pion form factor with twisted mass QCD

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We apply the background field method to calculate the moments of the pion two-particles twist-3 distribution amplitude (DA) $\phi_p(\xi)$ in QCD sum rules. In this paper,we do not use the equation of motion for the quarks inside the pion…

High Energy Physics - Phenomenology · Physics 2009-11-10 Tao Huang , Xing-Hua Wu , Ming-Zhen Zhou

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 study the pion electromagnetic form factor in the modulus squared dispersion relation, and do the model independent extraction of the most important nonperturbative parameters in pion light-cone distribution amplitude. The motivation of…

High Energy Physics - Phenomenology · Physics 2023-07-26 Jian Chai , Shan Cheng , Jun Hua

Separated longitudinal and transverse structure functions for the reaction 1H(e,eprime pi+)n were measured in the momentum transfer region Q2=0.6-1.6 (GeV/c)**2 at a value of the invariant mass W=1.95 GeV. New values for the pion charge…

Nuclear Experiment · Physics 2009-04-15 J. Volmer

The $^{1}$H($e,e^\prime \pi^+$)n cross section was measured for a range of four-momentum transfer up to $Q^2$=3.91 GeV$^2$ at values of the invariant mass, $W$, above the resonance region. The $Q^2$-dependence of the longitudinal component…

Nuclear Experiment · Physics 2009-11-13 T. Horn

The light-front approach is applied to calculate the electromagnetic current for quark-antiquark bound states for the pion. The pion electromagnetic form factor is obtnaide from the "+" and "-" components of the electromagnetic current in…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. P. B. C. de Melo

The electric dipole form factor of the nucleon stemming from the QCD $\bar{\theta}$ term is calculated in chiral perturbation theory in leading order. To this order, the form factor originates from the pion cloud. Its momentum-dependence is…

Nuclear Theory · Physics 2009-11-11 W. H. Hockings , U. van Kolck

A new limit of pion form factor at very large $Q^2$ is obtained by using a pion wave function determined from an effective chiral field theory of mesons. It shows that when $Q^2>>(1.8GeV)^2$ the pion form factor reaches the asymptotic limit…

High Energy Physics - Phenomenology · Physics 2009-09-28 Bing An Li

We compute the electromagnetic form factors of the proton and neutron using lattice QCD with $N_f = 2 + 1 + 1$ twisted mass clover-improved fermions and quark masses tuned to their physical values. Three ensembles with lattice spacings of…

High Energy Physics - Lattice · Physics 2025-02-18 Constantia Alexandrou , Simone Bacchio , Giannis Koutsou , Bhavna Prasad , Gregoris Spanoudes

The form factors of the semileptonic $B\to \pi\pi\ell\bar\nu$ decay are calculated from QCD light-cone sum rules with the distribution amplitudes of dipion states. This method is valid in the kinematical region, where the hadronic dipion…

High Energy Physics - Phenomenology · Physics 2016-04-20 Christian Hambrock , Alexander Khodjamirian

Recent results on pion physics from lattice QCD are reviewed. We discuss quark mass dependences of pion mass and decay constant and compare them with the predictions from chiral perturbation theory. In particular we focus on the convergence…

High Energy Physics - Lattice · Physics 2014-11-20 Sinya Aoki

We present results on the Omega baryon electromagnetic form factors using N_f= 2 + 1 dynamical domain-wall fermion configurations corresponding to a pion mass of about 330 MeV. We construct appropriate sequential sources for the…

High Energy Physics - Lattice · Physics 2010-11-05 C. Alexandrou , T. Korzec , G. Koutsou , Y. Proestos

A unified set of predictions for pion and kaon elastic electromagnetic and gravitational form factors is obtained using a symmetry-preserving truncation of each relevant quantum field equation. A key part of the study is a description of…

High Energy Physics - Phenomenology · Physics 2023-11-28 Yin-Zhen Xu , Minghui Ding , Khépani Raya , Craig D. Roberts , José Rodríguez-Quintero , Sebastian M. Schmidt

We present a construction of the pion electromagnetic form factor where the transition from large-Nc Regge vector meson dominance models with infinitely many resonances to perturbative QCD is built in explicitly. The construction is based…

High Energy Physics - Phenomenology · Physics 2008-11-26 Enrique Ruiz Arriola , Wojciech Broniowski

We present a high-statistics lattice QCD determination of the valence parton distribution function (PDF) of the pion, with a mass of 300 MeV, using two very fine lattice spacings of $a=0.06$ fm and 0.04 fm. We reconstruct the $x$-dependent…

We present a lattice QCD calculation of the $\rho$ meson decay width via the $P$-wave scattering phase shift for the I=1 two-pion system. Our calculation uses full QCD gauge configurations for $N_f=2$ flavors generated using a…

High Energy Physics - Lattice · Physics 2012-08-27 PACS Collaboration , S. Aoki , M. Fukugita , K-I. Ishikawa , N. Ishizuka , K. Kanaya , Y. Kuramashi , Y. Namekawa , M. Okawa , K. Sasaki , A. Ukawa , T. Yoshié

We consider a bottom-up AdS/QCD model with a conformal exponential deformation $e^{k\,z^2}$ on a Lorentz invariant AdS background. In this model, we assume the conformal dimension associated with the operator that creates pions at the…

High Energy Physics - Phenomenology · Physics 2022-03-29 Miguel Angel Martin Contreras , Eduardo Folco Capossoli , Danning Li , Alfredo Vega , Henrique Boschi-Filho

Using QCD sum rules with nonlocal condensates the twist-2 pion distribution amplitude is determined by means of its moments and their confidence intervals, including also radiative corrections. An admissible set of pion distribution…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. P. Bakulev , S. V. Mikhailov , N. G. Stefanis

In the paper, we investigate the charmed meson rare decay process $D^+ \to \pi^+\nu\bar\nu$ by using QCD sum rules approach. Firstly, the pion twist-2 and twist-3 distribution amplitude $\xi$-moments $\langle\xi_{2;\pi}^n\rangle|_\mu$ up to…

High Energy Physics - Phenomenology · Physics 2024-01-09 Yu Chen , Hai-Bing Fu , Tao Zhong , Sheng-Bo Wu , Dong Huang

The form factor and the mean-square radius of the pion are calculated analytically from a parametrized form of a $q\bar q$ wave function. The numerical wave function was obtained previously by solving numerically an eigenvalue equation for…

High Energy Physics - Phenomenology · Physics 2009-11-07 Hans-Christian Pauli , Asmita Mukherjee