PT Journal
AU Molina, R
   Ruiz de Elvira, J
TI Light- and strange-quark mass dependence of the rho(770) meson revisited
SO Journal of High Energy Physics
JI J. High Energy Phys.
PY 2020
BP 017
EP 74pp
VL 11
IS 11
DI 10.1007/JHEP11(2020)017
LA English
DE Chiral Lagrangians; Lattice QCD
AB Recent lattice data on pi pi -scattering phase shifts in the vector-isovector channel, pseudoscalar meson masses and decay constants for strange-quark masses smaller or equal to the physical value allow us to study the strangeness dependence of these observables for the first time. We perform a global analysis on two kind of lattice trajectories depending on whether the sum of quark masses or the strange-quark mass is kept fixed to the physical point. The quark mass dependence of these observables is extracted from unitarized coupled-channel one-loop Chiral Perturbation Theory. This analysis guides new predictions on the rho (770) meson properties over trajectories where the strange-quark mass is lighter than the physical mass, as well as on the SU(3) symmetric line. As a result, the light- and strange-quark mass dependence of the rho (770) meson parameters are discussed and precise values of the Low Energy Constants present in unitarized one-loop Chiral Perturbation Theory are given. Finally, the current discrepancy between two- and three-flavor lattice results for the rho (770) meson is studied.
ER