Abstract
We have systematically investigated the mass spectrum and rearrangement decay properties of the exotic tetraquark states with four different flavors using a color-magnetic interaction model. Their masses are estimated by assuming that the $X(4140)$ is a $cs\bar{c}\bar{s}$ tetraquark state and their decay widths are obtained by assuming that the Hamiltonian for decay is a constant. According to the adopted method, we find that the most stable states are probably the isoscalar $bs\bar{u}\bar{d}$ and $cs\bar{u}\bar{d}$ with $J^P=0^+$ and $1^+$. The width for most unstable tetraquarks is about tens of MeVs, but that for unstable $cu\bar{s}\bar{d}$ and $cs\bar{u}\bar{d}$ can be around 100 MeV. For the $X(5568)$, our method cannot give consistent mass and width if it is a $bu\bar{s}\bar{d}$ tetraquark state. For the $I(J^P)=0(0^+),0(1^+)$ double-heavy $T_{bc}=bc\bar{u}\bar{d}$ states, their widths can be several MeVs.
Highlights
Since 2003, heavy quark exotic XYZ or Pc states have been observed in almost every year [1,2,3,4]
The Xð5568Þ claimed by the D0 Collaboration [18,19] is special in that it is a bsud or bsdu meson with valence quarks of four different flavors
In Ref. [48], we presented a study of the spectra of qqq Q (Q 1⁄4 c, b, q 1⁄4 u, d, s) systems in the color-magnetic interaction (CMI) model
Summary
Since 2003, heavy quark exotic XYZ or Pc states have been observed in almost every year [1,2,3,4]. To understand the natures of the exotic states, a large number of theoretical studies in the literature were performed, which include discussions about the hadron structures (molecules, compact multiquarks, kinematic effects, or other nonresonant interpretations), investigations on the production and decay properties, and developments of research methods [5,6,7,8,9,10,11,12,13,14,15,16,17] In these exotic states, the Xð5568Þ claimed by the D0 Collaboration [18,19] is special in that it is a bsud or bsdu meson with valence quarks of four different flavors. The last section gives some discussions and the summary of the present work
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have