Observation of the decay B^0 → J/ψ ω at Belle II
We measure the branching fraction of the decay B0→J/psi w using data collected with the Belle II detector at the SuperKEKB collider. The data contain (387+/-6)x 106 BB meson pairs produced in energy-asymmetric e+e- collisions at the Upsilon(4S) resonance. The measured branching fraction B(B0→J/psi w)=(2.16+/-0.30+/-0.14)x10-5, where the first uncertainty is statistical and the second is systematic, is more precise than previous results and constitutes the first observation of the decay with a significance of 6.5 standard deviations
مجلة/صحيفة
PHYSICAL REVIEW D
Using data samples of 983.0 fb⁻¹ and 427.9 fb⁻¹ accumulated with the Belle and Belle II detectors operating at the KEKB and SuperKEKB asymmetric-energy e⁺e⁻ colliders,…