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Long distance contributions to the eta_b => Jpsi Jpsi decay

Pietro Santorelli
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Abstract

It was argued long ago that eta_b could be observed through the eta_b => Jpsi(=> mu+ mu-) Jpsi(=> mu+ mu-) decay chain. Recent calculations indicate that the width of eta_b into two Jpsi is almost 3 orders of magnitude smaller than the one into the D bar D*. We study the effects of final-state interactions due to the D bar D* intermediate state on the Jpsi Jpsi final state. We find that the inclusion of this contribution may enhance the short-distance branching ratio up to about 2 orders of magnitude.

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Pietro Santorelli. 2008-04-08. Long distance contributions to the eta_b => Jpsi Jpsi decay. https://doi.org/10.1103/physrevd.77.074012

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