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Related papers: Pion form factors with improved infrared factoriza…

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The QCD evolution of the pion distribution amplitude (DA) $\phi_\pi(x,Q^2)$ is computed for several commonly used models. Our analysis includes the nonperturbative form predicted by light-front holographic QCD, thus combining the…

High Energy Physics - Phenomenology · Physics 2011-08-12 Stanley J. Brodsky , Fu-Guang Cao , Guy F. de Teramond

We present results of a calculation of the electromagnetic pion form factor within a framework of QCD Sum Rules with nonlocal condensates and using a perturbative spectral density which includes \mathcal{O}(\alpha_s) contributions.

High Energy Physics - Phenomenology · Physics 2014-11-18 A. P. Bakulev , A. V. Pimikov , N. G. Stefanis

The pionic contribution to the g-2 of the muon involves a certain integral over the the modulus squared of F_\pi(t), the pion electromagnetic form factor. We extend techniques that use cut-plane analyticity properties of F_\pi(t) in order…

High Energy Physics - Phenomenology · Physics 2008-11-26 B. Ananthanarayan , S. Ramanan

We describe the present status of the pion distribution amplitude as originated from two sources: (i) a nonperturbative approach, based on QCD sum rules with nonlocal condensates, and (ii) a NLO QCD analysis of the CLEO data on…

High Energy Physics - Phenomenology · Physics 2009-11-10 A. P. Bakulev

We present results of a calculation of the electromagnetic pion form factor within the framework of QCD Sum Rules with nonlocal condensates, using a perturbative spectral density which includes $O(\alpha_s)$ contributions.

High Energy Physics - Phenomenology · Physics 2014-11-18 Alexander P. Bakulev , A. V. Pimikov , N. G. Stefanis

We compute the electromagnetic form factor of the pion using non-perturbatively O(a) improved Wilson fermions. The calculations are done for a wide range of pion masses and lattice spacings. We check for finite size effects by repeating…

We compare phenomenological values of the frozen QCD running coupling constant ($\alpha_s$) with two classes of solutions obtained through nonperturbative Schwinger-Dyson equations. We use these same solutions with frozen coupling constants…

High Energy Physics - Phenomenology · Physics 2009-11-07 A. C. Aguilar , A. Mihara , A. A. Natale

We present a theoretical parametrization of the nucleon electromagnetic form factors (FFs) based on a combination of chiral effective field theory and dispersion analysis. The isovector spectral functions on the two-pion cut are computed…

High Energy Physics - Phenomenology · Physics 2018-08-15 J. M. Alarcón , C. Weiss

We discuss the pion form factor calculation in QCD.We shortly consider the main points of the nonlocal condensate QCD sum rule approach and show its results for the pion form factor, $F_\pi(Q^2)$. These results are compared with predictions…

High Energy Physics - Phenomenology · Physics 2015-05-20 Alexander P. Bakulev

The recently evaluated two-pion contribution to the muon g-2 and the phase of the pion electromagnetic form factor in the elastic region, known from \pi\pi scattering by Fermi-Watson theorem, are exploited by analytic techniques for finding…

High Energy Physics - Phenomenology · Physics 2011-05-13 B. Ananthanarayan , Irinel Caprini , I. Sentitemsu Imsong

The pion wave function is discussed in the light of the recent CLEO data on the pion gamma transition form factor. It turns out that the wave function is close to the asymptotic form whereas wave functions strongly concentrated in the…

High Energy Physics - Phenomenology · Physics 2009-08-25 P. Kroll , M. Raulfs

We use the recently measured accurate BaBaR data on the modulus of the pion electromagnetic form factor, $F_\pi(t)$, up to an energy of 3 GeV, the I=1 $P$-wave phase of the $\pi\pi$ scattering amplitude up to the $\omega-\pi$ threshold, the…

High Energy Physics - Phenomenology · Physics 2012-06-20 I. Sentitemsu Imsong , B. Ananthanarayan , Irinel Caprini

We present an investigation of the electromagnetic pion form factor, $F_\pi(Q^2)$, at small values of the four-momentum transfer $Q^2$ ($\lesssim 0.25$ GeV$^2$), based on the gauge configurations generated by European Twisted Mass…

Dispersive representations of the pi-pi scattering amplitudes and pion form factors, valid at two-loop accuracy in the low-energy expansion, are constructed in the presence of isospin-breaking effects induced by the difference between the…

High Energy Physics - Phenomenology · Physics 2015-06-04 S. Descotes-Genon , M. Knecht

We analyze the radiative pion decay pi+ -> e+ nu_e gamma within nonlocal chiral quark models that include wave function renormalization. In this framework we calculate the vector and axial-vector form factors FV and FA at q^2=0 --where q^2…

High Energy Physics - Phenomenology · Physics 2011-04-28 D. Gomez Dumm , S. Noguera , N. N. Scoccola

We use dispersive techniques to address the behavior of the pion form factor as $Q^2 \to \infty$ and $Q^2 \to 0$. We perform the matching with the constraints of perturbative QCD and chiral perturbation theory in the high energy and low…

High Energy Physics - Phenomenology · Physics 2011-07-19 John F. Donoghue , Euy Soo Na

We report on our calculation of the pion electromagnetic form factor with two-flavors of dynamical overlap quarks. Gauge configurations are generated using the Iwasaki gauge action on a 16^3 \times 32 lattice at the lattice spacing of…

High Energy Physics - Lattice · Physics 2009-04-14 JLQCD collaboration , T. Kaneko , H. Fukaya , S. Hashimoto , H. Matsufuru , J. Noaki , T. Onogi , N. Yamada

We compute the Form Factors of both neutral and charged pion using a non-perturbative running of the strong coupling constant $\alpha_s$ obtained using a double-dilaton Holographic QCD model. These form factors remain poorly understood in…

High Energy Physics - Phenomenology · Physics 2026-04-13 Héctor Cancio , Pere Masjuan

The data analysis for the reaction H(e,e' pi^+)n, which was used to determine values for the charged pion form factor Fpi for values of Q^2=0.6-1.6 GeV^2, has been repeated with careful inspection of all steps and special attention to…

Recent data from high statistics experiments that have measured the modulus of the pion electromagnetic form factor from threshold to relatively high energies are used as input in a suitable mathematical framework of analytic continuation…

High Energy Physics - Phenomenology · Physics 2013-08-13 B. Ananthanarayan , I. Caprini , Diganta Das , I. Sentitemsu Imsong