Study of lattice QCD by large scale numerical simulations including dynamical quark effects

通过大规模数值模拟（包括动态夸克效应）研究晶格 QCD

• 批准号: 15540279
• 负责人: OKAWA Masanori
• 金额: $ 2.24万
• 依托单位: HIROSHIMA UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-15540279/
• 关键词: Lattice QCD; Dynamical quark; Hadron matrix element

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 hadronic matrix elements. In fact, in the quenched approximation where the dynamical quark loop effect is neglected, it has been shown that the evaluated hadron mass spectra deviate from experimental values by about 5-10%. It has also been shown recently that about half part of the deviation in hadron mass spectra observed in the quenched approximation disappears with the inclusion of the dynamical loop effect of u and d quarks. In the real world, however, there are three light quarks, u,d and s quarks, and it is important to verify if the remaining deviation disappears by the inclusion of the s quark loop effect. For this purpose we have made realistic (2+1) flavor QCD simulation with O(a) improved Wilson fermions in which the discretization error of lattice QCD simulation is known to be O(a^2) with a the lattice spacing. We have calculated hadron mass spectra on two lattices having lattice spacing a【approximately equal】 0.1fm and 0.12fm. We have extrapolated hadron masses to a=0 assuming a^2 dependence of hadron masses evaluated on lattices with finite a, and found that preliminary values of extrapolated hadron masses are consistent with experimental values. Evaluation of phenomenologically important various hadronic matrix elements such as decay constants have also been done including the dynamical loop effect of u and d quarks.

在格点QCD模拟中考虑动力学夸克圈效应是定量研究强相互作用和获得唯象重要的强子矩阵元的重要问题之一。事实上，在忽略动力学夸克圈效应的淬灭近似下，计算的强子质量谱与实验值的偏差约为5- 10%。最近的研究还表明，在猝灭近似下观测到的强子质量谱中，约有一半的偏差随着u和d夸克的动力学圈效应的加入而消失。然而，在真实的世界中，有三种轻夸克，u、d和s夸克，验证剩余的偏差是否因包含s夸克环效应而消失是很重要的。为此，我们用O（α）改进的Wilson费米子进行了现实的（2+1）味QCD模拟，其中格点QCD模拟的离散化误差为O（α ^2），且格点间距为a。我们计算了两个晶格间距为0.1fm和0.12fm的晶格上的强子质量谱。假设在有限a的晶格上计算的强子质量依赖于a^2，我们将强子质量外推到a=0，发现外推的强子质量的初步值与实验值一致。唯象重要的各种强子矩阵元素，如衰变常数的评估也已经完成，包括u和d夸克的动力学圈效应。

项目成果

S.Aoki: "B^0-B^^-^0 mixing in unquenched lattice QCD"Physical Review Letters. 91. 212001 1-212001 4 (2003)

S.Aoki：“B^0-B^^-^0 在未淬火晶格 QCD 中混合”物理评论快报。

Non-perturbative calculation of $Z_V$ and $Z_A$ in domain-wall QCD on a finite box

有限盒上磁畴壁 QCD 中 $Z_V$ 和 $Z_A$ 的非微扰计算

• 发表时间: 2004
• 期刊: Phys.Rev. D70
• 作者: S.Aoki;Shigeru Nishizaki;S.Aoki
• 通讯作者: S.Aoki

Non-perturbative O(a)-improvement of Wilson quark action in three-flavor QCD with plaquette gauge action

具有血小板规范作用的三味 QCD 中威尔逊夸克作用的非微扰 O(a) 改进

• 发表时间: 2005
• 期刊: Phys. Rev. D 71
• 作者: Aoki;W.;et al.;N.Yamada
• 通讯作者: N.Yamada

B(0)-B(0) mixing in unquenched lattice QCD.

• DOI: 10.1103/physrevlett.91.212001
• 发表时间: 2003-07
• 期刊: Physical review letters
• 影响因子: 8.6
• 作者: S. Aoki;M. Fukugita;S. Hashimoto;K. Ishikawa;N. Ishizuka;Y. Iwasaki;K. Kanaya;T. Kaneko;Y. Kuramashi;M. Okawa;T. Onogi;N. Tsutsui;A. Ukawa;N. Yamada;T. Yoshie

Light hadron spectroscopy in two-flavor QCD with small sea quark masses

小海夸克质量的双味 QCD 中的光强子光谱

• 发表时间: 2004
• 期刊: Phys. Rev. D 70
• 作者: K.Sadakane;T.Ohnishi;M.Ohkubo;Y.Takeda;Y.Takeda et al.;E.Shintani et al.;Tatsuyuki Takatsuka;S.Aoki;K.Sadakane et al.;Tatsuyuki Takatsuka;Y.Namekawa
• 通讯作者: Y.Namekawa