Anatomy of the ρ resonance from lattice QCD at the physical point

被引：0

作者：

孙玮 ^{[1
,2
]}

Andrei Alexandru ^{[3
]}

陈莹 ^{[1
,2
]}

Terrence Draper ^{[4
]}

刘朝峰 ^{[1
,2
]}

杨一玻 ^{[5
]}

机构：

[1] Institute of High Energy Physics,Chinese Academy of Sciences

[2] School of Physics,University of Chinese Academy of Sciences

[3] Department of Physics,George Washington University

[4] Department of Physics and Astronomy,University of Kentucky

[5] Department of Physics and Astronomy,Michigan State University

来源：

Chinese Physics C | 2018年 / 06期

关键词：

ρ; resonance; leptonic decay constant; renormalization;

D O I：

暂无

中图分类号：

O572.33 [介子];

学科分类号：

070202 ;

摘要：

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 mπ2. The slope is determined to be c1 =0.505（3）GeV-1, from which the valence πρ sigma term is extracted to be σπρval= 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 fρexp≈221 MeV through the relation fρexp=（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.

引用

页码：20 / 26

页数：7