The enhancement of the decay Υ ( 1 D ) → η Υ ( 1 S ) by the axial anomaly in QCD
نویسنده
چکیده
It is shown that the rates of the decays Υ(1 3 D 1) → η Υ(1S) and Υ(1 3 D 2) → η Υ(1S) should be comparable to and likely exceed that of the recently discussed in the literature two-pion transition Υ(1D) → π π Υ(1S). The reason for this behavior is that the discussed η transitions are enhanced by the contribution of the anomaly in the flavor singlet axial current in QCD.
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