Branching fraction measurements of B→ηcK decays

We study the decays B+→ηcK+ and B0→ηcK0, where the ηc is reconstructed in the KS0K±π∓ and K+K-π0 decay modes. Results are based on a sample of 86 million BB̅ pairs collected with the BABAR detector at the SLAC e+e- B Factory. We measure the product of branching fractions B(B+→ηcK+)×B(ηc→KK̅ π)=(7.40±0.50±0.70)×10-5 and B(B0→ηcK0)×B(ηc→KK̅ π)=(6.48±0.85±0.71)×10-5, where the first error is statistical and the second is systematic. In addition, we search for B⃗ηcK events with ηc→2(K+K-) and ηc→φφ and determine the ηc decay branching fraction ratios B(ηc→2(K+K-))/B(ηc→KK̅ π)=(2.3±0.7±0.6)×10-2 and B(ηc→φφ)/B(ηc→KK̅ π)=(5.5±1.4±0.5)×10-2.