Improved Measurements of Branching Fractions for η_c → φφ and ωφ


Using (223.7 ± 1.4) x 10⁶ J/ψ events accumulated with the BESIII detector, we study η_c decays to φφ and ωφ final states. The branching fraction of η_c → φφ is measured to be Br(η_c → φφ) = (2.5 ± 0.3_{-0.7}^{+0.3} ± 0.6) X 10⁻³, where the first uncertainty is statistical, the second is systematic, and the third is from the uncertainty of Br(J/ψ → γη_c). No significant signal for the double Okubo-Zweig-Iizuka suppressed decay of η_c → ωϕ is observed, and the upper limit on the branching fraction is determined to be Br(η_c → ωϕ) < 2.5 × 10⁻⁴ at the 90% confidence level.



Branching fractions (Nuclear physics), Particles (Nuclear physics)--Decay, Particles (Nuclear physics)—Helicity, Mesons, Nuclear spin

This work is supported in part by National Key Basic Research Program of China under Contract No. 2015CB856700; National Natural Science Foundation of China (NSFC) under Contracts No. 11505034, No. 11375205, No. 11565006, No. 11647309, No. 11125525, No. 11235011, No. 11322544, No. 11335008, No. 11425524, and 11305090; Joint Large-Scale Scientific Facility Funds of the NSFC and CAS under Contracts No. 11179007, No. U1232201, and No. U1332201; CAS under Contracts No. KJCX2-YW-N29 and No. KJCX2-YW-N45; German Research Foundation DFG under Collaborative Research Center (CRC) Contracts No. 1044 and No. FOR 2359; Koninklijke Nederlandse Akademie van Wetenschappen (KNAW) under Contract No. 530-4CDP03; Ministry of Development of Turkey under Contract No. DPT2006K-120470; Russian Foundation for Basic Research under Contract No. 14-07-91152; U.S. Department of Energy under Contracts No. DE-FG02-05ER41374, No. DE-SC-0010504, No. DE-SC0012069, and No. DESC0010118; and WCU Program of National Research Foundation of Korea under Contract No. R32-2008-000-10155-0.


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