Using samples of 102 million Υ(1S) and 158 million Υ(2S) events collected with the Belle detector, we study exclusive hadronic decays of these two bottomonium resonances to KS0K+π- and charge-conjugate (c.c.) states, π+π-π0π0, and π+π-π0, and to the two-body Vector-Pseudoscalar (K*(892)0K̄0+c.c., K*(892)-K ++c.c., ωπ0, and ρπ) final states. For the first time, signals are observed in the modes Υ(1S)→KS0K+π -+c.c., π+π-π0π0, and Υ(2S)→π+π-π0π0, and evidence is found for the modes Υ(1S)→π+π-π0, K*(892)0K̄0+c.c., and Υ(2S)→KS0K +π-+c.c. Branching fractions are measured for all the processes, while 90% confidence level upper limits on the branching fractions are also set for the modes with a statistical significance of less than 3σ. The ratios of the branching fractions of Υ(2S) and Υ(1S) decays into the same final state are used to test a perturbative QCD prediction for Okubo-Zweig-Iizuka-suppressed bottomonium decays.
|Journal||Physical Review D - Particles, Fields, Gravitation and Cosmology|
|State||Published - 23 Jul 2013|