格点量子色动力学寻找H双重子

The H-dibaryon, one of the most famous candidates of exotic-hadron, is considered as the lowest state in the doubly strange dibaryon sector. It is one of the most challenging works to search for the H-dibaryon in the physics of strong interaction. Lattice Quantum Chromodynamics(Lattice QCD)provides us a powerful tool to study the hadron spectra, QCD phase structure and hadronic interactions from first principles. We will investigate the H-dibaryon on lattice with two approaches. In the first approach, the mass of the H-dibaryon is extracted directly from its correlation functions, which has already been done in quenched QCD in our preliminary works and will be extended to full QCD to reduce the systematic errors. In order to reduce the contaminations of the excited states, the Levenberg-Marquardt algorithm will be adopted to fit the hadronic correlation functions. In the second approch, once the baryon-baryon(BB) potentials are extracted from the Nambu-Bethe-Salpeter(NBS) wave function, the observables, such as the binding energy of the H-dibaryon, the scattering phase shift and the scattering length, can be carried out from the potentials. Our simulation will be performed on anisotropic lattices with several lattice spacings and some pseudo-scalar meson masses. Quark mass dependences of the binding energy of the H-dibaryon, the scattering phase shift and the scattering length will be studied, that will help us to understand the chiral behavior of these observables. The physics of these observables in the continuum limit is one of the major subjects in our works. In summary, our research work on the dibaryon will provides the experimenters some valuable information and help us to further understand the hadron physics.

H双重子一直以来被认为是最有可能存在的奇异强子之一，寻找该粒子是强相互作用领域的一项富有挑战性的工作。格点量子色动力学为我们提供一个强大的从第一原理出发的工具去研究强子质量谱、QCD相结构和强子相互作用。我们拟采取两套方案在full QCD下研究H双重子：第一套方案是通过H双重子的关联函数直接计算它的质量，并采用Levenberg-Marquardt算法拟合强子的关联函数以减少激发态的信噪；第二套方案，根据Nambu-Bethe-Salpeter波函数计算双重子作用势，进一步求出束缚能量、散射相移和散射长度等观测量。H双重子在连续极限下的相关性质是我们研究的重点。我们的工作可以为粒子物理实验提供有参考价值的数据，也有助于更加深刻认识理解强相互作用。

多夸克态、混杂态、胶球，这些有别于传统介子和重子的强子，被称为新强子。新强子的研究有助于我们更加深入认识理解基本粒子的内部性质和相互作用，对认识物质世界的本质以及宇宙的起源演化有不可或缺的帮助。格点量子色动力学为我们提供一个强大的从第一原理出发的工具去研究强子质量谱、QCD 相结构和强子相互作用，具有先天的优越性。H 双重子一直以来被认为是最有可能存在的新强子之一，寻找该粒子是强相互作用领域的一项富有挑战性的工作。我们的研究表明，H双重子是稳定的束缚态，其束缚能量为几十MeV，这为实验提供了一个重要的参考和依据。另外，我们使用格点QCD还研究了璨夸克成分混杂态介子0^{-+} 和1^{--} ，以及相应的传统介子。结果表明，这些混杂态介子与相应的传统介子可以混合，混合成分是各占50%。