Study of Lattice QCD by numerical simulations including dynamical quark effects

通过包括动态夸克效应在内的数值模拟研究晶格 QCD

• 批准号: 11640294
• 负责人: OKAWA Masanori
• 金额: $ 1.86万
• 依托单位: HIROSHIMA UNIVERSITY (2001-2002)The High Energy Accelerator Research Organization (1999-2000)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11640294/
• 关键词: Lattice QCD; Hadron matrix element; dynamical quark

Including dynamical quark loop effects in lattice QCD simulations is one of the most important problem to make quantitative study of strong interaction and to obtain phenomenologically important hadron matrix elements. In fact it has been shown that in the quenched approximation where the dynamical quark loop effect is neglected the evaluated hadron mass spectrums deviate from experimental values by about 10%. For N_f = 2 QCD where the dynamical u and d quark effects are taken into account we have made large scale simulations with the exact hybrid Monte Carlo (HMC) simulation algorithm. It has been shown that a large part of the deviation in hadron mass spectrum observed in the quenched approximation disappears with the inclusion of N_f = 2 dynamical quark effect. In the real world, however, there are three light quarks and it is important to make simulations including the s quark loop effect. For this purpose we have developed efficient exact simulation algorithm for odd number of O(a) improved Wilson fermions. We have made first realistic N_f = 3 QCD simulation with O(a) improved Wilson fermions and estimated mass spectrum for various hadrons, from which fundamental lattice QCD parameters such as lattice spacing and quark masses are determined.

在晶格QCD模拟中包含动态夸克环效应是定量研究强相互作用和获得现象学上重要的强子矩阵元素的最重要问题之一。事实上，已经表明，在忽略动态夸克环效应的淬灭近似中，评估的强子质谱与实验值偏差约 10%。对于 N_f = 2 QCD，其中考虑了动态 u 和 d 夸克效应，我们使用精确的混合蒙特卡罗 (HMC) 模拟算法进行了大规模模拟。研究表明，在淬灭近似中观察到的强子质谱偏差的很大一部分随着 N_f = 2 动态夸克效应的加入而消失。然而，在现实世界中，存在三个轻夸克，因此进行包括夸克环效应在内的模拟非常重要。为此，我们为奇数个 O(a) 改进的威尔逊费米子开发了高效的精确模拟算法。我们使用 O(a) 改进的威尔逊费米子和估计的各种强子的质谱进行了首次真实的 N_f = 3 QCD 模拟，从中确定了基本晶格 QCD 参数，例如晶格间距和夸克质量。

项目成果

T.Manke: "Quark effects on quarkonia"Physical Review D. 62・11. 114508-1-13 (2000)

T.Manke：“夸克对夸克尼亚的影响”物理评论D. 62・11（2000）。

A.Ali Khan: "Equation of state in finite-temperature QCD with two flavors of improved Wilson quarks"Physical Review. D64. 074510-1-074510-17 (2001)

A.Ali Khan：“有限温度 QCD 中的状态方程，具有两种改进的威尔逊夸克”物理评论。

Y. Namekawa: "Thermodynamics of SU(3) gauge theory on anisotropic lattices"Physical Review. D64, 074507. 1-13 (2001)

Y. Namekawa：“各向异性晶格上 SU(3) 规范理论的热力学”物理评论。

T. Manke: "Hybrid quarkonia with dynamical sea quarks"Physical Review. D64, 097505. 1-4 (2001)

T. Manke：“混合夸克尼亚与动态海夸克”物理评论。

A. Ali Khan: "Chiral properties of domain-wall quarks in quenched QCD"Physical Review. D63, 114504. 1-19 (2001)

A. Ali Khan：“猝灭 QCD 中域壁夸克的手性特性”物理评论。