Electromagnetic form factor of pion from N_f=2+1 dynamical flavor QCD

Details Electromagnetic form factor of pion from N_f=2+1 dynamical flavor QCD Electromagnetic form factor of pion from N_f=2+1 dynamical flavor QCD

2011-02-17

arxiv.org/abs/1102.3652v1

JHEP 1104:122,2011

Physics

High Energy Physics

High Energy Physics - Lattice

28 pages, 14 figures

Scientific paper

10.1007/JHEP04(2011)122

We present a calculation of the electromagnetic form factor of the pion in $N_f=2+1$ flavor lattice QCD. Calculations are made on the PACS-CS gauge field configurations generated using Iwasaki gauge action and Wilson-clover quark action on a $32^3\times64$ lattice volume with the lattice spacing estimated as $a=0.0907(13)$ fm at the physical point. Measurements of the form factor are made using the technique of partially twisted boundary condition to reach small momentum transfer as well as periodic boundary condition with integer momenta. Additional improvements including random wall source techniques and a judicious choice of momenta carried by the incoming and outgoing quarks are employed for error reduction. Analyzing the form factor data for the pion mass at $M_\pi \approx 411$ MeV and 296 MeV, we find that the NNLO SU(2) chiral perturbation theory fit yields $=0.441 \pm 0.046 {\rm fm}^2$ for the pion charge radius at the physical pion mass. Albeit the error is quite large, this is consistent with the experimental value of $0.452\pm 0.011 {\rm fm}^2$. Below $M_\pi\approx 300$ MeV, we find that statistical fluctuations in the pion two- and three-point functions become too large to extract statistically meaningful averages on a $32^3$ spatial volume. We carry out a sample calculation on a $64^4$ lattice with the quark masses close to the physical point, which suggests that form factor calculations at the physical point become feasible by enlarging lattice sizes to $M_\pi L\approx 4$.

Affiliated with

Also associated with

No associations

Rating

Electromagnetic form factor of pion from N_f=2+1 dynamical flavor QCD does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Electromagnetic form factor of pion from N_f=2+1 dynamical flavor QCD, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Electromagnetic form factor of pion from N_f=2+1 dynamical flavor QCD will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-381010