Search for the decay B+-> K+ v(v)over-bar RID C-5223-2009 RID C-5719-2008 RID D-1055-2009 RID A-2675-2009

We search for the rare flavor-changing neutral-current decay B+ -> K+ v (v) over tilde in a data sample of 82 fb(-1) collected with the BABAR detector at the PEP-II B-factory. Signal events are selected by examining the properties of the system recoiling against either a reconstructed hadronic or semileptonic charged-B decay. Using these two independent samples we obtain a combined limit of B(B+ -> K+ v (v) over bar) < 5.2 x10(-5) at the 90% confidence level. In addition, by selecting for pions rather than kaons, we obtain a limit of B(B+ -> pi(+) v (v) over bar) < 1.0 x 10(-4) using only the hadronic B reconstruction method.

We search for the rare flavor-changing neutral-current decay B+ → K+ νν̄ in a data sample of 82 fb-1 collected with the BABAR detector at the PEP-II S-factory. Signal events are selected by examining the properties of the system recoiling against either a reconstructed hadronic or semileptonic charged-B decay. Using these two independent samples we obtain a combined limit of ℬ(B+ →K+ νν̄) ≤ 5.2 × 10-5 at the 90% confidence level In addition, by selecting for pions rather than kaons, we obtain a limit of ℬ(B+ → π+ νν̄) < 1.0 × 10-4 using only the hadronic B reconstruction method. © 2005 The American Physical Society.