Chiral extrapolation of lattice data for the hyperfine splittings of heavy mesons

Abstract

Hyperfine splittings between the heavy vector (D*, B*) and pseudoscalar (D, B) mesons have been calculated numerically in lattice QCD, where the pion mass (which is related to the light quark mass) is much larger than its physical value. Naive linear chiral extrapolations of the lattice data to the physical mass of the pion lead to hyperfine splittings which are smaller than experimental data. In order to extrapolate these lattice data to the physical mass of the pion more reasonably, we apply the effective chiral perturbation theory for heavy mesons, which is invariant under chiral symmetry when the light quark masses go to zero and heavy quark symmetry when the heavy quark masses go to infinity. This leads to a phenomenological functional form with three parameters to extrapolate the lattice data. It is found that the extrapolated hyperfine splittings are even smaller than those obtained using linear extrapolation. We conclude that the source of the discrepancy between lattice data for hyperfine splittings and experiment must lie in non-chiral physics.

27 pages, 6 figures

References in corpus (2)

• Chiral extrapolation of lattice moments of proton quark distributions
• Chiral Behaviour of the Rho Meson in Lattice QCD

Cited by in corpus (6)

• Chiral perturbation theory for heavy hadrons and chiral effective field theory for heavy hadronic molecules
• Light quark mass dependence of the $D$ and $D_s$ decay constants
• Chiral extrapolation of lattice data for B-meson decay constant
• Chiral Extrapolation of Lattice Data for Heavy Baryons
• Chiral Extrapolation of Lattice Data for Heavy Meson Hyperfine Splittings
• The effect of sea quarks on the mass of the charm quark from Lattice QCD