Υ(1s) → γf2(1270) Decay
نویسنده
چکیده
Decay Υ(1s) → γf2(1270) is studied by an approach in which the tensor meson, f2(1270), is strongly coupled to gluons. Besides the strong suppression of the amplitude Υ(1s) → γgg, gg → f2 by the mass of b-quark, d-wave dominance in Υ(1s) → γf2(1270) is revealed from this approach, which provides a large enhancement. The combination of these two factors leads to larger B(Υ(1s) → γf2(1270)). The decay rate of Υ(1s) → γf2(1270) and the ratios of the helicity amplitudes are obtained and they are in agreement with data.
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