Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8185478 | Nuclear Physics B - Proceedings Supplements | 2013 | 4 Pages |
Abstract
We estimate the masses of the 1ââ heavy four-quark and molecule states by combining exponential Laplace (LSR) and finite energy (FESR) sum rules known perturbatively to lowest order (LO) in αs but including non-perturbative terms up to the complete dimension-six condensate contributions. We use double ratio of sum rules (DRSR) for determining the SU(3) breakings terms. The SU(3) mass-splittings of about (50-110) MeV and the ones of about (250-300) MeV between the lowest ground states and their 1st radial excitations are (almost) heavy-flavour independent. The mass predictions summarized in Table 2 are compared with the ones in the literature (when available) and with the three Yc(4260,4360,4660) and Yb(10890)1ââ experimental candidates. We conclude that the lowest observed state cannot be a pure1ââ four-quark nor a pure molecule but may result from their mixings. We extend the above analyzes to the 0++ four-quark and molecule states which are about (0.5-1) GeV heavier than the corresponding 1ââ states, while the splittings between the 0++ lowest ground state and the 1st radial excitation is about (300-500) MeV. We complete the analysis by estimating the decay constants of the 1ââ and 0++ four-quark states. Our predictions can be tested using some alternative non-perturbative approaches or/and at LHCb or some other hadron factories.
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Nuclear and High Energy Physics
Authors
R.M. Albuquerque, F. Fanomezana, S. Narison, A. Rabemananjara,