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arXiv · 0810.0366

Single eta production in heavy quarkonia: breakdown of multipole expansion

Yu. A. Simonov·A. I. Veselov
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Abstract

The $η$ production in the $(n,n')$ bottomonium transitions $Υ(n) \to Υ(n') η, $ is studied in the method used before for dipion heavy quarkonia transitions. The widths $Γ_η(n,n')$ are calculated without fitting parameters for $n=2,3,4,5, n'=1$. Resulting $Γ_η(4,1)$ is found to be large in agreement with recent data. Multipole expansion method is shown to be inadequate for large size systems considered.

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Yu. A. Simonov, A. I. Veselov. 2008-12-26. Single eta production in heavy quarkonia: breakdown of multipole expansion. https://doi.org/10.1016/j.physletb.2009.02.025

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