Understanding the internal structures of X(4140), X(4274), X(4500) and X(4700)

Hua-Xing Chen,Xiang Liu,Wei Chen,Shi-Lin Zhu,Er-Liang Cui

doi:10.1140/epjc/s10052-017-4737-5

Abstract

We investigate the newly observed X(4500) and X(4700) based on the diquark–antidiquark configuration within the framework of QCD sum rules. Both of them may be interpreted as the D-wave csbar{c}bar{s} tetraquark states of J^P = 0^+, but with opposite color structures, which is remarkably similar to the result obtained in Chen and Zhu (Phys Rev D 83:034010, 2011) that X(4140) and X(4274) can be both interpreted as the S-wave csbar{c}bar{s} tetraquark states of J^P = 1^+, also with opposite color structures. However, the extracted masses and these suggested assignments to these X states do depend on these running quark masses where m_s (2,text{ GeV }) = 95 pm 5 MeV and m_c (m_c) = 1.23 pm 0.09 GeV. As a byproduct, the masses of the hidden-bottom partner states of X(4500) and X(4700) are extracted to be both around 10.64 GeV, which can be searched for in the Upsilon phi invariant mass distribution.

Highlights

Very recently the LHCb Collaboration confirmed X (4140) and X (4274) in the J/ψφ invariant mass distribution and determined their spin-parity quantum numbers to be both J P = 1++ [7,8,9,10]
We propose to search for them in the Υφ invariant mass distribution with the running of LHC at 13 TeV and the forthcoming BelleII experiment
The central value corresponds to MB2 = 2.05 GeV2 and s0 = 22 GeV2, and the uncertainty comes from the Borel mass MB, the threshold value s0, the strange and charm quark masses, and the various condensates. This value is consistent with the experimental mass of the X (4500) [7,8,9,10], supporting it to be a D-wave cscstetraquark state of J P = 0+

Summary

Introduction

[1] that X (4140) and X (4274) can be both interpreted as S-wave tetraquark states with the quark content cscsand J P = 0+: X (4140) consists of one S-wave “good” diquark and one S-wave “bad” antidiquark, having the antisymmetric color structure [3 ̄c]cs ⊗[3c]cs; the X (4274) consists of two similar S-wave diquarks, but having the symmetric color structure [6c]cs ⊗ [6 ̄c]cs. We investigate the bottom partner states of X (4500) and X (4700), and we extract their masses to find them to be both around 10.64 GeV.

Results

Conclusion