Color halo scenario of charmonium-like hybrids

Journal Article · 15 August 2021 · Chinese Physics C, High Energy Physics and Nuclear Physics

DOI: https://doi.org/10.1088/1674-1137/ac0ee2 · OSTI ID:1959367

Ma, Yunheng ^[1]; Sun, Wei ^[2]; Chen, Ying ^[1]; Gong, Ming ^[1]; Liu, Zhaofeng ^[1]

---

1. Chinese Academy of Sciences (CAS), Beijing (China)
2. Chinese Academy of Sciences (CAS), Beijing (China); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

The internal structures of J^PC =1^--,(o,1,2)^-+ charmonium-like hybrids are investigated under lattice QCD in the quenched approximation. We define the Bethe-Salpeter wave function (Φn(r)) in the Coulomb gauge as the matrix element of a spatially extended hybrid-like operator ($$\bar{c}cg$$) between the vacuum and n-th state for J^PC, with r being the spatial separation between a localized $$\bar{c}c$$ component and the chromomagnetic strength tensor. These wave functions exhibit some similarities for states with the aforementioned different quantum numbers, and their r-behaviors (no node for the ground states and one node for the first excited states) imply that r can be a meaningful dynamical variable for these states. Additionally, the mass splittings of the ground states and first excited states of charmonium-like hybrids in these channels are obtained for the first time to be approximately 1.2-1.4 GeV. These results do not support the flux-tube description of heavy-quarkonium-like hybrids in the Born-Oppenheimer approximation. In contrast, a charmonium-like hybrid can be viewed as a "color halo" charmonium for which a relatively localized color octet $$\bar{c}c$$ is surrounded by gluonic degrees of freedom, which can readily decay into a charmonium state along with one or more light hadrons. The color halo picture is compatible with the decay properties of Y (42600) and suggests LHCb and BelleII to search for (0,1,2)^-+ charmonium-like hybrids in Xc0,1,2N and J/ψω(φ) final states.

• Research Organization: Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Nuclear Physics (NP)
• Grant/Contract Number: AC05-06OR23177
• OSTI ID: 1959367
• Report Number(s): DOE/OR/23177-5777; JLAB-THY-21-3605; arXiv:1910.09819
• Journal Information: Chinese Physics C, High Energy Physics and Nuclear Physics, Journal Name: Chinese Physics C, High Energy Physics and Nuclear Physics Journal Issue: 9 Vol. 45; ISSN 1674-1137
• Publisher: IOP PublishingCopyright Statement
• Country of Publication: United States
• Language: English