We propose a strategy to access the qq component of the p resonance in lattice QCD. Through a mixed action formalism（overlap valence on domain wall sea）, the energy of the qq component is derived at different valenc...We propose a strategy to access the qq component of the p resonance in lattice QCD. Through a mixed action formalism（overlap valence on domain wall sea）, the energy of the qq component is derived at different valence quark masses, and shows a linear dependence on mπ^2. The slope is determined to be c1 =0.505（3）GeV^-1, from which the valence πρ sigma term is extracted to be σ（πρ）^val= 9.82（6） MeV using the Feynman-Hellman theorem. At the physical pion mass, the mass of the qq component is interpolated to be mρ = 775.9±6.0±1.8 MeV, which is close to the p resonance mass. We also obtain the leptonic decay constant of the qq component to be fρ-=208.5±5.5±0.9 MeV, which can be compared with the experimental value fρ^exp≈221 MeV through the relation fρ^exp=（1/2）Zfρ±, with Zρ≈1.13 being the on-shell wavefunction renormalization of p owing to the ρ-π interaction. We emphasize that mρand fρ of the qq component, which are obtained for the first time from QCD, can be taken as the input parameters of p in effective field theory studies where p acts as a fundamental degree of freedom.展开更多
基金Supported in part by the U.S.DOE Grant No.DE-SC0013065the National Nature Science Foundation of China(NSFC)(11335001,11575196,11575197,11621131001)(CRC110 by DFG and NSFC)+3 种基金by the National Science Foundation CAREER(PHY-1151648)U.S.DOE(DE-FG02-95ER40907)CAS Center for Excellence in Particle Physics(CCEPP)for their supportused the resources of the Oak Ridge Leadership Computing Facility at the Oak Ridge National Laboratory,which is supported by the Office of Science of the U.S.Department of Energy(DE-AC05-00OR22725)
文摘We propose a strategy to access the qq component of the p resonance in lattice QCD. Through a mixed action formalism（overlap valence on domain wall sea）, the energy of the qq component is derived at different valence quark masses, and shows a linear dependence on mπ^2. The slope is determined to be c1 =0.505（3）GeV^-1, from which the valence πρ sigma term is extracted to be σ（πρ）^val= 9.82（6） MeV using the Feynman-Hellman theorem. At the physical pion mass, the mass of the qq component is interpolated to be mρ = 775.9±6.0±1.8 MeV, which is close to the p resonance mass. We also obtain the leptonic decay constant of the qq component to be fρ-=208.5±5.5±0.9 MeV, which can be compared with the experimental value fρ^exp≈221 MeV through the relation fρ^exp=（1/2）Zfρ±, with Zρ≈1.13 being the on-shell wavefunction renormalization of p owing to the ρ-π interaction. We emphasize that mρand fρ of the qq component, which are obtained for the first time from QCD, can be taken as the input parameters of p in effective field theory studies where p acts as a fundamental degree of freedom.
