Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA.
Phys Rev Lett. 2014 Jun 6;112(22):222001. doi: 10.1103/PhysRevLett.112.222001. Epub 2014 Jun 3.
Many of the XYZ mesons discovered in the last decade can be identified as bound states of a heavy quark and antiquark in Born-Oppenheimer (BO) potentials defined by the energy of gluon and light-quark fields in the presence of static color sources. The mesons include quarkonium hybrids, which are bound states in excited flavor-singlet BO potentials, and quarkonium tetraquarks, which are bound states in BO potentials with light-quark+antiquark flavor. The deepest hybrid potentials are known from lattice QCD calculations. The deepest tetraquark potentials can be inferred from lattice QCD calculations of static adjoint mesons. Selection rules for hadronic transitions are derived and used to identify XYZ mesons that are candidates for ground-state energy levels in the BO potentials for charmonium hybrids and tetraquarks.
过去十年中发现的许多 XYZ 介子可以被识别为在玻恩-奥本海默（Born-Oppenheimer，BO）势中的重夸克和反夸克束缚态，这些 BO 势由存在静态色源时的胶子和轻夸克场的能量定义。介子包括夸克混杂态，它们是在激发的单味 BO 势中的束缚态，以及夸克四态，它们是在带有轻夸克+反夸克味的 BO 势中的束缚态。最深的混杂势是从格点 QCD 计算中得到的。最深的四态势可以从格点 QCD 对静态伴随介子的计算中推断出来。推导了强子跃迁的选择定则，并将其用于识别 XYZ 介子，这些介子是在夸克混杂态和四态的 BO 势中的基态能级的候选者。
