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arXiv · hep-ph/0006296

A possible hadronic excess in psi(2S) decay and rho-pi puzzle

Abstract

We examine the so-called rho-pi puzzle of the psi(2S) decay by incorporating two inputs: One is the relative phase between the one-photon and the gluon decay amplitude, and the other is a possible anomaly in the inclusive nonelectromagnetic decay rate of psi(2S). We propose the possibility that in the psi(2S) decay a hadronic decay process of long distance origin is important in addition to the short-distance decay process. The amplitude of this additional process should nearly cancel the three-gluon amplitude in the exclusive psi(2S)---> 1-0- and turn the sum dominantly real in contrast to the J/psi decay. We present general consequences of this mechanism and then briefly look into two models which possibly explain the course of this additional amplitude.

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BibTeXRIS

M. Suzuki. 2000-11-09. A possible hadronic excess in psi(2S) decay and rho-pi puzzle. https://doi.org/10.1103/physrevd.63.054021

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