Multipion systems in lattice QCD and the three-pion interaction.
The ground-state energies of 2, 3, 4, and 5 pi(+)'s in a spatial volume V approximately (2.5 fm)(3) are computed with lattice QCD. By eliminating the leading contribution from three-pi(+) interactions, particular combinations of these n-pi(+) ground-state energies provide precise extractions of the pi(+)pi(+) scattering length in agreement with that obtained from calculations involving only two pi(+)'s. The three-pi(+) interaction can be isolated by forming other combinations of the n-pi(+) ground-state energies. We find a result that is consistent with a repulsive three-pi(+) interaction for m_(pi) less, similar352 MeV.
Beane
Silas R
SR
Department of Physics, University of New Hampshire, Durham, New Hampshire 03824-3568, USA.
Detmold
William
W
Luu
Thomas C
TC
Orginos
Kostas
K
Savage
Martin J
MJ
Torok
Aaron
A