PT Journal
AU Blanton, TD
   Romero-Lopez, F
   Sharpe, SR
TI I=3 Three-Pion Scattering Amplitude from Lattice QCD
SO Physical Review Letters
JI Phys. Rev. Lett.
PY 2020
BP 032001
EP 7pp
VL 124
IS 3
DI 10.1103/PhysRevLett.124.032001
LA English
AB We analyze the spectrum of two- and three-pion states of maximal isospin obtained recently for isosymmetric QCD with pion mass M approximate to 200 MeV in Horz and Hanlon, [Phys. Rev. Lett. 123, 142002 (2019)]. Using the relativistic three-particle quantization condition, we find similar to 2 sigma evidence for a nonzero value for the contact part of the 3 pi(+) (I = 3) scattering amplitude. We also compare our results to leading-order chiral perturbation theory. We find good agreement at threshold and some tension in the energy dependent part of the 3 pi(+) scattering amplitude. We also find that the 2 pi(+) (I = 2) spectrum is fit well by an s-wave phase shift that incorporates the expected Adler zero.
ER