Heavy Hybrids from NRQCD
نویسندگان
چکیده
We present a quenched lattice calculation for the lowest lying bb̄g-hybrid states in the framework of NRQCD using the leading order Hamiltonian up to O(mv). We demonstrate the existence of a nearly degenerate rotational band of states with an excitation energy approximately 1.6 GeV above the Υ ground state. This lies around the BB̄ J threshold but well above the BB̄-threshold. Therefore a heavy hybrid signal may well be detected if the centre-of-mass energy in B-factories is raised a few hundred MeV to coincide with other resonances above the 4S state. Our prediction is consistent with most phenomenological models and lattice calculations carried out in the static limit.
منابع مشابه
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