First Observation of the Zb0(10610) in a Dalitz Analysis of Y(5S) - Y(nS) pi0 pi0

Abstract

We report the first observation of Y(5S) - Y(nS) pi0 pi0 decays. The neutral partner of the Zb+-(10610), the Zb0(10610) decaying to Y(2,3S) pi0, is observed for the first time with a 6.5 sigma significance using a Dalitz analysis of Y(5S) - Y(2,3S) pi0 pi0 decays. The results are obtained with a 121.4 fb-1 data sample collected with the Belle detector at the Y(5S) resonance at the KEKB asymmetric-energy e+e- collider.