格点 QCD 中的大多数奇异双介子。

Most Strange Dibaryon from Lattice QCD.

机构信息

RIKEN Nishina Center, RIKEN, Saitama 351-0198, Japan.

Center for Gravitational Physics, Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502, Japan.

出版信息

Phys Rev Lett. 2018 May 25;120(21):212001. doi: 10.1103/PhysRevLett.120.212001.

DOI:10.1103/PhysRevLett.120.212001

PMID:29883161

Abstract

The ΩΩ system in the ^{1}S_{0} channel (the most strange dibaryon) is studied on the basis of the (2+1)-flavor lattice QCD simulations with a large volume (8.1 fm)^{3} and nearly physical pion mass m_{π}≃146 MeV at a lattice spacing of a≃0.0846 fm. We show that lattice QCD data analysis by the HAL QCD method leads to the scattering length a_{0}=4.6(6)({-0.5}^{+1.2}) fm, the effective range r{eff}=1.27(3)({-0.03}^{+0.06}) fm, and the binding energy B{ΩΩ}=1.6(6)(_{-0.6}^{+0.7}) MeV. These results indicate that the ΩΩ system has an overall attraction and is located near the unitary regime. Such a system can be best searched experimentally by the pair-momentum correlation in relativistic heavy-ion collisions.

摘要

在（2+1）- flavors 格点 QCD 模拟的基础上，我们研究了^{1}S_{0}通道中的 ΩΩ 系统（最奇异的双重子），该模拟采用了大体积（8.1 fm）^{3}和近乎物理的π介子质量 m_{π}≃146 MeV，格点间距为 a≃0.0846 fm。我们表明，通过 HAL QCD 方法对格点 QCD 数据分析得到的散射长度 a_{0}=4.6(6)({-0.5}^{+1.2}) fm，有效范围 r{eff}=1.27(3)({-0.03}^{+0.06}) fm，以及束缚能 B{ΩΩ}=1.6(6)(_{-0.6}^{+0.7}) MeV。这些结果表明，ΩΩ 系统具有整体吸引力，并且位于幺正区域附近。这种系统可以通过相对论性重离子碰撞中的对动量关联来进行最佳的实验搜索。