Scalar tetraquark state candidates: X(3915), X(4500) and X(4700)

Zhi-Gang Wang

doi:10.1140/epjc/s10052-017-4640-0

Zhi-Gang Wang

Open Access

https://doi.org/10.1140/epjc/s10052-017-4640-0

Copy DOI

Abstract

In this article, we tentatively assign the X(3915) and X(4500) to be the ground state and the first radial excited state of the axialvector–diquark–axialvector–antidiquark type scalar csbar{c}bar{s} tetraquark states, respectively, assign the X(4700) to be the ground state vector–diquark–vector–antidiquark type scalar csbar{c}bar{s} tetraquark state, and study their masses and pole residues with the QCD sum rules in detail by calculating the contributions of the vacuum condensates up to dimension 10. The numerical results support assigning the X(3915) and X(4500) to be the ground state and the first radial excited state of the axialvector–diquark–axialvector–antidiquark type scalar csbar{c}bar{s} tetraquark states, respectively, and assigning the X(4700) to be the ground state vector–diquark–vector–antidiquark type scalar csbar{c}bar{s} tetraquark state.

Highlights

In 2009, X (4140) was first observed by the CDF collaboration in the J/ψφ mass spectrum in the B+ → J/ψ φ K + decays with a statistical significance in excess of 3.8σ [1]
The D0 collaboration confirmed the X (4140) in the B+ → J/ψφ K + decays with a statistical significance of 3.1σ [4]
In Ref. [8], we study the masses and pole residues of the J PC = 1+± hidden charmed tetraquark states with the QCD sum rules

Summary

Introduction

In 2009, X (4140) was first observed by the CDF collaboration in the J/ψφ mass spectrum in the B+ → J/ψ φ K + decays with a statistical significance in excess of 3.8σ [1]. In 2011, the CDF collaboration confirmed the Y (4140) in the B± → J/ψ φ K ± decays with a statistical significance greater than 5σ , and observed evidence for the new resonance X (4274) with an approximate statistical significance of 3.1σ [2]. In 2013, the CMS collaboration confirmed X (4140) in the J/ψφ mass spectrum in the B± → J/ψφ K ± decays, and fitted the structure to an S-wave relativistic Breit–Wigner line-shape above a three-body phase-space nonresonant component with a statistical significance exceeding 5σ [3]. [8], we study the masses and pole residues of the J PC = 1+± hidden charmed tetraquark states with the QCD sum rules. Detailed analysis based on the QCD sum rules indicates that it is unreasonable to assign

78 Page 2 of 10

78 Page 4 of 10

Numerical results and discussions

78 Page 6 of 10

78 Page 8 of 10

Conclusion