https://doi.org/10.1140/epja/i2015-15158-0
Letter
The scalar radius of the pion from lattice QCD in the continuum limit
1
PRISMA Cluster of Excellence and Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, 55099, Mainz, Germany
2
Helmholtz Institute Mainz, Johannes Gutenberg-Universität Mainz, 55099, Mainz, Germany
* e-mail: guelpers@kph.uni-mainz.de
Received:
20
August
2015
Accepted:
19
November
2015
Published online:
9
December
2015
We extend our study (Phys. Rev. D 89, 094503 (2014)) of the pion scalar radius in two-flavour lattice QCD to include two additional lattice spacings as well as lighter pion masses, enabling us to perform a combined chiral and continuum extrapolation. We find discretisation artefacts to be small for the radius, and confirm the importance of the disconnected diagrams in reproducing the correct chiral behaviour. Our final result for the scalar radius of the pion at the physical point is fm2, corresponding to a value of
for the low-energy constant
of NLO chiral perturbation theory.
© SIF, Springer-Verlag Berlin Heidelberg, 2015