ISSN - 15507998, Physical Review D - Particles, Fields, Gravitation and Cosmology, 2004, vol. 70, p. 011101-1
Branching fraction measurements of B → ηcK decays
We study the decays B+ → ηcK+ and B0 → ηcK0, where the ηc is reconstructed in the KS 0K ±π∓ and K+K- π0 decay modes. Results are based on a sample of 86 B B̄ 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→KK̄π)= (7.40±0.50±0.70)×10-5 and B(B 0→ηcK0) ×B(ηc→KK̄π)=(6.48±0.85±0.71) ×10-5, where the first error is statistical and the second is systematic, In addition, we search for B → ηcK events with ηc→2(K+K-) and ηc→ φφ and determine the ηc decay branching fraction ratios B(ηc →(K+K-)) /B(ηc→KK̄π)=(2.3±0.7±0.6) ×10-2 and B(ηc→φφ) /B(ηc→KK̄π)=(5.5±1.4±0.5) ×10-2.