A family of double-beauty tetraquarks:Axial-vector state T-bb;(us)

• 来源期刊: 中国物理C（英文版）
• 年，卷（期）: 2021,（1）
• 所属期刊栏目: PARTICLES AND FIELDS
• 页码范围: 67-81
• 页数: 15页
• 语种: 英文
• DOI: 10.1088/1674-1137/abc16d

摘要

The spectroscopic parameters and decay channels of the axial-vector tetraquark Tbb;(us)(in what follows,TAVb:(s))are explored using the quantum chromodynamics(QCD)sum rule method.The mass and coupling of this state are calculated using two-point sum rules by taking into account various vacuum condensates,up to 10 dimensions.Our prediction for the mass of this state m =(10215 ± 250)MeV confirms that it is stable with respect to strong and electromagnetic decays and can dissociate to conventional mesons only via weak transformations.We investigate the dominant semileptonic TAVb:(s)→ Z0b:(s)√vl and nonleptonic TAVb:(s)→ Z0b:(s)M decays of TAVb:(s).In these processes,Z0b:(s)is a scalar tetraquark[bc][us]built of a color-triplet diquark and an antidiquark,whereas M is one of the vector mesons p-,K*(892),D*(2010)-,and D*-s.To calculate the partial widths of these decays,we use the QCD three-point sum rule approach and evaluate the weak transition form factors Gi(i = 0,1,2,3),which govern these processes.The full width Tfull =(12.9 ± 2.1)x 10-8 MeV and the mean lifetime τ = 5.1+-0.99 fs of the tetraquark TAVb:(s)are computed us-ing the aforementioned weak decays.The obtained information about the parameters of TAVb:(s)and Z:(s)is useful for experimental investigations of these double-heavy exotic mesons.