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↗

DOE OSTI2011

Search for CP and P violating pseudoscalar decays into ππ

Not Available

Ablikim, M.↗

DOE OSTI2011

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.↗

DOE OSTI2011

Study of χ cJ radiative decays into a vector meson

Not Available

Ablikim, M.↗

DOE OSTI2011

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↗

DOE OSTI2011

Study of a 0 0 ( 980 ) − f 0 ( 980 ) mixing

Not Available

Ablikim, M.↗

DOE OSTI2011

First observation of the decays χ c J → π 0 π 0 π 0 π 0

Not Available

Ablikim, M.↗

DOE OSTI2011

Measurement of the matrix element for the decay η ′ → η π + π −

Not Available

Ablikim, M.↗

DOE OSTI2010

ATF2 Commissioning

ATF2 is a final-focus test beam line that attempts to focus the low-emittance beam from the ATF damping ring to a beam size of about 37 nm, and at the same time to demonstrate nm beam stability, using numerous advanced beam diagnostics and feedback tools. The construction is well advanced and beam commissioning of ATF2 has started in the second half of 2008. ATF2 is constructed and commissioned by ATF international collaborations with strong US, Asian and European participation.

Seryi, Andrei↗