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arXiv · hep-ph/0203191

Radiative Decay of $Υ$ into a Scalar Glueball

X. -G. He·H. -Y. Jin·J. P. Ma
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Abstract

We study the radiative decay of $Υ$ into a scalar glueball $Υ\to γG_s$ using QCD factorization. We find that for this process the non-perturbative effects can be factorized into a matrix element well defined in non-relativistic QCD (NRQCD) and the gluon distribution amplitude. The same NRQCD matrix element appears also in leptonic decay of $Υ$ and therefore can be determined from data. In the asymptotic limit the gluon distribution amplitude is known up to a normalization constant. Using a QCD sum-rule calculation for the normalization constant, we obtain $Br(Υ\to γG_s)$ to be in the range $(1\sim 2)\times 10^{-3}$. We also discuss some of the implications for $Υ\to γf_i$ decays. Near future data from CLEO-III can provide crucial information about scalar glueball properties.

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X. -G. He, H. -Y. Jin, J. P. Ma. 2002-07-01. Radiative Decay of $Υ$ into a Scalar Glueball. https://doi.org/10.1103/physrevd.66.074015

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