Search for ψ(2S)→ηcπ+π-π0

Abstract

Using 5.63pb-1 of data accumulated at the ψ(2S) resonance with the CLEO III and CLEO-c detectors corresponding to 3.08×106 ψ(2S) decays, a search is performed for the decay ψ(2S)→ηcπ+π-π0 to test a theoretical prediction based upon the assumption that the cc̄ pair in the ψ(2S) does not annihilate directly into three gluons but rather survives before annihilating. No signal is observed, and a combined upper limit from six ηc decay modes is determined to be B(ψ(2S)→ηcπ+π-π0) ≤1.0×10-3 at 90% C.L. This upper limit is about an order of magnitude below the theoretical expectation. © 2007 The American Physical Society.