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Related papers: The pion form factor in improved lattice QCD

200 papers

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

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

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

In this report we present the status of the Mainz group's lattice QCD calculation of the pion transition form factor, which describes the interaction of an on-shell pion with two off-shell photons. This form factor is the main ingredient in…

High Energy Physics - Lattice · Physics 2023-11-14 Jonna Koponen , Antoine Gérardin , Harvey B. Meyer , Konstantin Ottnad , Georg von Hippel

We present a comprehensive analysis of the electromagnetic form factors of the nucleon from a lattice simulation with two flavors of dynamical O(a)-improved Wilson fermions. A key feature of our calculation is that we make use of an…

The pion electromagnetic form factor is calculated within the QCD light-cone sum rule method and using a renormalon model for the higher twist distribution amplitudes (DAs). The theoretical predictions are compared with the experimental…

High Energy Physics - Phenomenology · Physics 2009-11-11 S. S. Agaev

We present a lattice QCD calculation of the pion scalar form factor and associated radii with fully controlled systematics. Lattice results are computed on a large set of 17 gauge ensembles with $N_f=2+1$ Wilson Clover-improved sea quarks.…

High Energy Physics - Lattice · Physics 2025-03-27 Konstantin Ottnad , Georg von Hippel

We calculate the pion transition form factor ${\cal F}_{\pi^0\gamma^*\gamma^*}(q_1^2,q_2^2)$, which describe the interaction of an on-shell pion with two off-shell photons, using lattice QCD simulations with two degenerate flavors of…

High Energy Physics - Lattice · Physics 2016-12-07 Antoine Gérardin , Harvey B. Meyer , Andreas Nyffeler

This letter is an investigation of the pion form factor utilizing recently developed effective field theory techniques. The primary results reported are: Both the transition and electromagnetic form factors are corrected at order…

High Energy Physics - Phenomenology · Physics 2009-11-10 Ira Z. Rothstein

The introduction of partially twisted boundary conditions allows weak and electromagnetic form factors to be evaluated at specified values of the hadronic momenta (and hence momentum transfers) in lattice simulations. We present and…

High Energy Physics - Lattice · Physics 2009-11-13 P. A. Boyle , J. M. Flynn , A. Juttner , C. T. Sachrajda , J. M. Zanotti

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 present results for Monte Carlo calculations of the electromagnetic vector and scalar form factors of the pion in a quenched simulation. We work at a lattice spacing of 0.15 fm and use two lattice volumes up to a spatial size of 2.4 fm.…

High Energy Physics - Lattice · Physics 2007-05-23 Stefano Capitani , Christof Gattringer , C. B. Lang

The two gravitational form factors of the pion, $A^{\pi}(t)$ and $D^{\pi}(t)$, are computed as functions of the momentum transfer squared $t$ in the kinematic region $0\leq -t< 2~\text{GeV}^2$ on a lattice QCD ensemble with quark masses…

High Energy Physics - Lattice · Physics 2023-12-12 Daniel C. Hackett , Patrick R. Oare , Dimitra A. Pefkou , Phiala E. Shanahan

We present new lattice results of the K -> pion semileptonic form factors obtained from simulations with two flavors of dynamical twisted-mass fermions, using pion masses as light as 260 MeV. Our main result is f+(0) = 0.9560 (84), which,…

High Energy Physics - Lattice · Physics 2019-08-13 V. Lubicz , F. Mescia , S. Simula , C. Tarantino

We present a calculation of the pion form factor using overlap fermions on 2+1-flavor domain-wall configurations on a $24^3\times 64$ lattice with $a=0.11 \, {\rm{fm}}$ and on a $32^3 \times 64$ lattice with $a=0.143 \, {\rm{fm}}$ generated…

High Energy Physics - Lattice · Physics 2018-10-31 Gen Wang , Jian Liang , Terrence Draper , Keh-Fei Liu , Yi-Bo Yang

The conservation of the isovector axial current in lattice QCD with massless Wilson quarks is studied to one-loop order of perturbation theory. Following a strategy described in a previous publication, the O($a$) counterterm required for…

High Energy Physics - Lattice · Physics 2016-08-15 M. Lüscher , P. Weisz

The pion electromagnetic form factor at spacelike momentum transfer is calculated in relativistic impulse approximation using the Covariant Spectator Theory. The same dressed quark mass function and the equation for the pion bound-state…

High Energy Physics - Phenomenology · Physics 2014-01-09 Elmar P. Biernat , Franz Gross , M. T. Peña , Alfred Stadler

We present the current status of the computation of the form factor $f_+ (q^2)$ for the semi-leptonic decay $\mathrm B_\mathrm s \to \mathrm K \ell \nu$ by the ALPHA collaboration. We use gauge configurations which were generated as part of…

High Energy Physics - Lattice · Physics 2014-11-17 Felix Bahr , Fabio Bernardoni , John Bulava , Anosh Joseph , Alberto Ramos , Hubert Simma , Rainer Sommer

The Global Color-symmetry Model of QCD is extended to deal with a background electromagnetic field and the associated conserved current is identified for composite $\bar{q}q$ pion modes of the model. Although the analysis is limited to tree…

Nuclear Theory · Physics 2008-11-26 M. R. Frank , P. C. Tandy

Lattice QCD can contribute to the search for new physics in b -> s decays by providing first-principle calculations of B -> K(*) form factors. Preliminary results are presented here which complement sum rule determinations by being done at…

High Energy Physics - Phenomenology · Physics 2015-03-17 Zhaofeng Liu , Stefan Meinel , Alistair Hart , Ron R. Horgan , Eike H. Müller , Matthew Wingate