Experimental study of X-b(2P)->pi pi X-b(1P)

We have searched for the di-pion transition chi(b)(2P) -> pi pi chi(b)(1P) in the CLEO III sample of Upsilon(3S) decays in the exclusive decay chain: Upsilon(3S) -> gamma chi(b)(2P), chi(b)(2P) -> pi pi chi(b)(1P), chi(b)(1P) -> gamma Upsilon(1S), Upsilon(1S) -> l(+)l(-). Our studies include both pi(+)pi(-) and pi(0)pi(0), each analyzed both in fully-reconstructed events and in events with one pion undetected. We show that the null hypothesis is not substantiated. Under reasonable assumptions, we find the partial decay width to be Gamma(chi(b)(2P) -> pi pi chi(b)(1P)) = (0.83 +/- 0.22 +/- 0.08 +/- 0.19) keV, with the uncertainties being statistical, internal CLEO systematics, and common systematics from outside sources.