Albaladejo_etal2012
ArticleInAPeriodical
Springer
2012
Journal of High Energy Physics
08
8
http://arxiv.org/abs/arXiv:1205.3582
http://arxiv.org/abs/arXiv:1205.3582
https://doi.org/10.1007/JHEP08(2012)071
071-22pp
AlbaladejoM
OllerJA
OsetE
RiosG
RocaL
Finite volume treatment of pi pi scattering and limits to phase shifts extraction from lattice QCD
We study theoretically the effects of finite volume for pi pi scattering in order to extract physical observables for infinite volume from lattice QCD. We compare three different approaches for pi pi scattering (lowest order Bethe-Salpeter approach, N/D and inverse amplitude methods) with the aim of studying the effects of the finite size of the box in the potential of the different theories, specially the left-hand cut contribution through loops in the crossed t, u-channels. We quantify the error made by neglecting these effects in usual extractions of physical observables from lattice ()CD spectrum. We conclude that for pi pi phase-shifts in the scalar-isoscalar channel up to 800 MeV this effect is negligible for box sizes bigger than 2,5m(pi)(-1) and of the order of 5% at around 1.5 – 2m(pi)(-1). For isospin 2 the finite size effects can reach up to 10% for that energy. We also quantify the error made when using the standard Luscher method to extract physical observables from lattice QCD, which is widely used in the literature but is an approximation of the one used in the present work.WOS:000309883600014exported from refbase (https://references.ific.uv.es/refbase/show.php?record=1214), last updated on Tue, 11 Dec 2012 14:44:13 +0000