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Geng, C.

Publications and source records attributed to Geng, C..

264 records · Page 15

Observation of {chi}{sub c1} Decays into Vector Meson Pairs {phi}{phi}, {omega}{omega}, and {omega}{phi}

Using (106{+-}4)x10{sup 6} {psi}(3686) events accumulated with the BESIII detector at the BEPCII e{sup +}e{sup -} collider, we present the first measurement of decays of {chi}{sub c1} to vector meson pairs {phi}{phi}, {omega}{omega}, and {omega}{phi}. The branching fractions are measured to be (4.4{+-}0.3{+-}0.5)x10{sup -4}, (6.0{+-}0.3{+-}0.7)x10{sup -4}, and (2.2{+-}0.6{+-}0.2)x10{sup -5}, for {chi}{sub c1}{yields}{phi}{phi}, {omega}{omega}, and {omega}{phi}, respectively, which indicates that the hadron helicity selection rule is significantly violated in {chi}{sub cJ} decays. In addition, the measurement of {chi}{sub cJ}{yields}{omega}{phi} provides the first indication of the rate of doubly OZI-suppressed {chi}{sub cJ} decay. Finally, we present improved measurements for the branching fractions of {chi}{sub c0} and {chi}{sub c2} to vector meson pairs.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Observation of χ cJ decaying into the pp̄K⁺K⁻ final state

First measurements of the decays of the three χ cJ states to pp̄K⁺K⁻ final states are presented. Intermediate Φ→K⁺K⁻ and Λ(1520)→pK⁻ resonance states are observed, and branching fractions for χ cJ →p̄K⁺Λ(1520), Λ(1520)Λ¯¯¯(1520), and Φpp̄ are reported. We also measure branching fractions for direct χ cJ →pp̄K⁺K⁻ decays. These are first observations of χ cJ decays to unstable baryon resonances and provide useful information about the χ cJ states. The experiment uses samples of χ cJ mesons produced via radiative transitions from 106×10⁶ ψ' mesons collected in the BESIII detector at the BEPCII e⁺e⁻ collider.

Ablikim, M.↗

Confirmation of the X(1835) and Observation of the Resonances X(2120) and X(2370) in J/{psi}{yields}{gamma}{pi}{sup +}{pi}{sup -}{eta}'

With a sample of (225.2{+-}2.8)x10{sup 6} J/{psi} events registered in the BESIII detector, J/{psi}{yields}{gamma}{pi}{sup +}{pi}{sup -}{eta}' is studied using two {eta}{sup '} decay modes: {eta}{sup '}{yields}{pi}{sup +}{pi}{sup -}{eta} and {eta}{sup '}{yields}{gamma}{rho}{sup 0}. The X(1835), which was previously observed by BESII, is confirmed with a statistical significance that is larger than 20{sigma}. In addition, in the {pi}{sup +}{pi}{sup -}{eta}' invariant-mass spectrum, the X(2120) and the X(2370), are observed with statistical significances larger than 7.2{sigma} and 6.4{sigma}, respectively. For the X(1835), the angular distribution of the radiative photon is consistent with expectations for a pseudoscalar.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗