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Related papers: Pion form factor with chirally improved fermions

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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

A continuum approach to quark-antiquark bound-states is used to determine the electromagnetic form factors of pion-like mesons with masses $m_{0^-}/{\rm GeV}=0.14$, $0.47$, $0.69$, $0.83$ on a spacelike domain that extends to $Q^2 \lesssim…

Nuclear Theory · Physics 2018-12-05 Muyang Chen , Minghui Ding , Lei Chang , Craig D. Roberts

We present a formula that allows one to calculate the pion form factor in the timelike region 2mpi <= sqrt{s} <= 4mpi in lattice QCD. The form factor quantifies the contribution of two-pion states to the vacuum polarization. It must be…

High Energy Physics - Lattice · Physics 2012-04-04 Harvey B. Meyer

We present a calculation of the scalar, vector and tensor pion and kaon form factors using one ensemble of two degenerate light, a strange and a charm quark ($N_f=2+1+1$) of maximally twisted mass fermions with clover improvement. The quark…

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 report preliminary results from an analysis of the pion scalar form factor computed on a set of the $\mathrm{tr}[M]=\mathrm{const}$ CLS gauge ensembles with $N_f=2+1$ Wilson Clover-improved sea quarks. The calculations are carried out…

High Energy Physics - Lattice · Physics 2024-01-17 Konstantin Ottnad , Georg von Hippel

We perform a nonperturbative lattice calculation of the complex phase and modulus of the pion form factor in the timelike momentum region using the finite-volume technique. We use two ensembles of 2+1-flavor overlap fermion at pion masses…

High Energy Physics - Lattice · Physics 2015-03-18 Xu Feng , Sinya Aoki , Shoji Hashimoto , Takashi Kaneko

We develop a methodology that enables us to extract accurately the electromagnetic Delta form factors and their momentum dependence. We test our approach in the quenched approximation as a preparation for a study using dynamical fermions.…

High Energy Physics - Lattice · Physics 2008-11-26 Constantia Alexandrou , Tomasz Korzec , Theodoros Leontiou , John W. Negele , Antonios Tsapalis

Moments of generalised parton distributions can be related to off-forward matrix elements of local operators. We calculate a few of the leading twist matrix elements for the pion on the lattice. The simulations are performed using two…

High Energy Physics - Lattice · Physics 2008-11-26 D. Brömmel , M. Diehl , M. Göckeler , Ph. Hägler , R. Horsley , D. Pleiter , P. E. L. Rakow , A. Schäfer , G. Schierholz , J. M. Zanotti

The charge form factor of the pion is calculated in lattice QCD. The non-perturbatively improved Sheikholeslami-Wohlert action is used together with the $\mathcal{O}(a)$ improved vector current. Other choices for the current are examined.…

High Energy Physics - Lattice · Physics 2009-11-10 J. van der Heide , J. Koch , E. Laermann

We calculate the scalar form factor of the pion using two dynamical flavors of non-perturbatively $\mathcal{O}(a)$-improved Wilson fermions, including both the connected and the disconnected contribution to the relevant correlation…

High Energy Physics - Lattice · Physics 2014-05-14 Vera Gülpers , Georg von Hippel , Hartmut Wittig

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

We have started a program to compute the electromagnetic form factors of mesons. We discuss the techniques used to compute the pion form factor and present preliminary results computed with domain wall valence fermions on MILC asqtad…

High Energy Physics - Lattice · Physics 2014-11-17 LHPC Collaboration , Frederic D. R. Bonnet , Robert G. Edwards , George T. Fleming , Randy Lewis , David G. Richards

The electromagnetic pion form factor, $F_\pi(q^2)$, is calculated for spacelike-$q^2$ in impulse approximation using a confining quark propagator, $S$, and a dressed quark-photon vertex, $\Gamma_\mu$, obtained from realistic,…

High Energy Physics - Phenomenology · Physics 2010-03-04 Craig D. Roberts

We calculate the pion vector and scalar form factors in two-flavor QCD. Gauge configurations are generated with dynamical overlap quarks on a 16^3 x 32 lattice at a lattice spacing of 0.12 fm with sea quark masses down to a sixth of the…

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

We evaluate the isovector nucleon electromagnetic form factors in quenched and full QCD on the lattice using Wilson fermions. In the quenched theory we use a lattice of spatial size 3 fm at beta=6.0 enabling us to reach low momentum…

High Energy Physics - Lattice · Physics 2008-11-26 C. Alexandrou , G. Koutsou , J. W. Negele , A. Tsapalis

Lattice results on the N to Delta electromagnetic, axial-vector and pseudoscalar form factors are evaluated using dynamical staggered sea quarks and domain wall valence quarks for pion masses in the range of 580-350 MeV, as well as,…

High Energy Physics - Lattice · Physics 2017-08-23 C. Alexandrou

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 calculate the electromagnetic pion form factor in lattice QCD with 2+1 flavors of the dynamical overlap quarks. Up and down quark masses are set below their physical values so that the system is in the so-called epsilon regime with the…

High Energy Physics - Lattice · Physics 2014-09-02 H. Fukaya , S. Aoki , S. Hashimoto , T. Kaneko , H. Matsufuru , J. Noaki

We present our calculations of the electromagnetic form factor of pions. We explore the properties of pion form factor at momentum transfer larger than previous studies by including more combinations of source and sink momenta and using…

High Energy Physics - Lattice · Physics 2010-12-13 Pai-hsien Jennifer Hsu , George T. Fleming