Pion vector form factor from lattice QCD at the physical point - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Physical Review D Année : 2018

Pion vector form factor from lattice QCD at the physical point

C. Alexandrou
  • Fonction : Auteur
S. Bacchio
  • Fonction : Auteur
P. Dimopoulos
  • Fonction : Auteur
J. Finkenrath
  • Fonction : Auteur
R. Frezzotti
  • Fonction : Auteur
K. Jansen
  • Fonction : Auteur
B. Kostrzewa
  • Fonction : Auteur
F. Sanfilippo
  • Fonction : Auteur
S. Simula
  • Fonction : Auteur
C. Urbach
  • Fonction : Auteur
U. Wenger
  • Fonction : Auteur

Résumé

We present an investigation of the electromagnetic pion form factor, Fπ(Q2), at small values of the four-momentum transfer Q2 (≲0.25  GeV2), based on the gauge configurations generated by the European Twisted Mass Collaboration with Nf=2 twisted-mass quarks at maximal twist including a clover term. Momentum is injected using nonperiodic boundary conditions and the calculations are carried out at a fixed lattice spacing (a≃0.09  fm) and with pion masses equal to its physical value, 240 MeV and 340 MeV. Our data are successfully analyzed using chiral perturbation theory at next-to-leading order in the light-quark mass. For each pion mass two different lattice volumes are used to take care of finite size effects. Our final result for the squared charge radius is ⟨r2⟩π=0.443(29)  fm2, where the error includes several sources of systematic errors except the uncertainty related to discretization effects. The corresponding value of the SU(2) chiral low-energy constant ℓ¯6 is equal to ℓ¯6=16.2(1.0).

Dates et versions

hal-01703780 , version 1 (08-02-2018)

Identifiants

Citer

C. Alexandrou, S. Bacchio, P. Dimopoulos, J. Finkenrath, R. Frezzotti, et al.. Pion vector form factor from lattice QCD at the physical point. Physical Review D, 2018, 97 (1), pp.014508. ⟨10.1103/PhysRevD.97.014508⟩. ⟨hal-01703780⟩
76 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Mastodon Facebook X LinkedIn More