A Candidate for $1^{--}$ Strangeonium Hybrid

We propose that the recently observed structure at 2175MeV by the Babar Collaboration is a $1^{--}$ strangeonium hybrid, and we investigate this interpretation from both the flux tube model and the constituent gluon model. The decay patterns and decay width in the flux tube model and the constituent gluon model (for the "gluon excited" hybrid) are very similar. The tetraquark hypothesis is not favored by the available experimental data. The crucial test of our scenario is suggested, furthermore, the promising channels which can discriminate the hybrid interpretation from the tetraquark are also suggested.
Comment: 20 pages, 7 figures