Analysis of finite size effects on the decay constants of heavy mesons

Abstract

Finite size effects on the decay constants of heavy pseudoscalar mesons (D and B mesons) are analyzed in the continuum limit. This study applies to the scaling limit of lattice QCD with dynamical light fermions. For large enough volume it is possible to determine the finite size effects by means of an effective field theory for both light and heavy mesons (chiral perturbation theory). The finite size effects are due to the presence of the light mesons (pions). It is shown that the existence of excited states in the heavy meson system can lead to important contributions to the effects. This is analyzed by including heavy vector mesons.