First observation of the Z(b)(0)(10610) in a Dalitz analysis of Upsilon(10860) -˃ Upsilon(nS)pi(0)pi(0)

Abstract

We report the first observation of Upsilon(10860) -> Upsilon(1, 2, 3S)pi(0)pi(0) decays. The neutral partner of the Z(1/b)(10610), the Z(b)(0)(10610) decaying to Upsilon(2, 3S)pi(0), is observed for the first time with a 6.5 sigma significance using a Dalitz analysis of Upsilon(10860) -> Upsilon (2, 3S)pi(0)pi(0) decays. The results are obtained with a 121.4 fb(-1) data sample collected with the Belle detector at the Upsilon(10860) resonance at the KEKB asymmetric- energy e(+)e(-) collider.