Two-Body B meson decays to η and η′: Observation of B→η′K

Abstract

In a sample of 6.6×106 produced B mesons we have observed decays B→η′K, with branching fractions B(B+→η′K)=(6.5+1.5-1.4±0.9)×10-5 and B(B0→η′K)=(4.7+2.7-2.0±0.9)×10-5. We have searched with comparable sensitivity for 17 related decays to final states containing an η or η′ meson accompanied by a single particle or low-lying resonance. Our upper limits for these constrain theoretical interpretations of the B→η′K signal. © 1998 The American Physical Society.