Hybrid static potentials and properties of heavy hybrid mesons from lattice QCD

杂化介子的量子数不同于夸克模型的量子数。它们是QCD预测的状态，胶子以一种不平凡的方式起作用。研究这种奇异介子是目前实验和理论粒子物理学中的一个热门话题。特别是在理论方面，非摄动预测是必要的，以最终解释当前存在的和未来的实验数据的财富。利用晶格QCD研究杂化介子的一种方法是计算杂化静态势。这些势被定义为具有无限重夸克和无限重反夸克的扇区中的基态能量，它们在空间上由胶子通量管分隔并连接，实现了非平凡量子数。这样的系统非常接近具有重价夸克的杂化介子。我们计划使用相当精细的晶格间距对这些混合静态势进行现代完全动态精度的晶格QCD计算，特别是为了更好地解决这些势的短程部分。在第二步中，我们将使用得到的混合静态势作为非相对论性Schrödinger方程的非微扰输入，这些方程的解可以预测混合介子的质量和其他性质。我们还计划探索关于这些计算的概念改进，特别是考虑到重夸克自旋的影响，这在过去一直被忽视，尽管它们的贡献预计是结合能的很大一部分。

Hybrid mesons have quantum numbers different from quark model quantum numbers. They are states predicted by QCD, where gluons contribute in a non-trivial way. Investigating such exotic mesons is currently a hot topic in experimental and theoretical particle physics. In particular on the theoretical side non-perturbative predictions are necessary, to conclusively interpret the wealth of currently existing and future experimental data.One approach to study hybrid mesons using lattice QCD is to compute hybrid static potentials. Such potentials are defined as the energy of the ground state in a sector with an infinitely heavy quark and an infinitely heavy antiquark, spatially separated and connected by a gluonic flux tube, which realizes the non-trivial quantum numbers. Such systems are quite close to hybrid mesons with heavy valence quarks. We plan to perform modern fully dynamical precision lattice QCD computations of these hybrid static potentials using rather fine lattice spacings, in particular to better resolve the short range part of these potentials.In a second step we will use the obtained hybrid static potentials as non-perturbative input for non-relativistic Schrödinger equations, whose solutions yield predictions for masses and other properties of hybrid mesons. We also plan to explore conceptual improvements regarding these calculations, in particular taking into account the effects of the heavy quark spins, which have always been neglected in the past, even though their contribution is expected to be a significant fraction of the binding energy.