Now showing items 108-127 of 231

    • Observation and Study of the Baryonic B-Meson Decays B→D^{(*)}pp̅ (π)(π) 

      Del Amo Sanchez, P.; Lees, J. P.; Poireau, V.; Prencipe, E.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Izen, Joseph M.; Lou, Xinchou; BaBar Collaboration (American Physical Society, 2012-05-30)
      We present results for B-meson decay modes involving a charm meson, protons, and pions using 455×10⁶ BB̄ pairs recorded by the BaBar detector at the SLAC PEP-II asymmetric-energy e⁺e⁻ collider. The branching fractions ...
    • Observation of a Charged Charmoniumlike Structure in e⁺e⁻ → (D*D̅*)^± π^∓ at √s=4.26 GeV 

      Ablikim, M.; Achasov, M. N.; Albayrak, O.; Ambrose, D. J.; An, F. F.; An, Q.; Bai, J. Z.; Lou, Xinchou (American Physical Society, 2014-04-02)
      We study the process e⁺e⁻ → (D*D̅*)^± π^∓ at a center-of-mass energy of 4.26 GeV using a 827 pb⁻¹ data sample obtained with the BESIII detector at the Beijing Electron Positron Collider. Based on a partial reconstruction ...
    • Observation of a Neutral Charmoniumlike State Z_c(4025)⁰ in e⁺e⁻ → (D*D̅*)⁰ π⁰ 

      Ablikim, M.; Achasov, M. N.; Ai, X. C.; Albayrak, O.; Albrecht, M.; Ambrose, D. J.; Amoroso, A.; Lou, Xinchou; BESIII Collaboration (2015-10)
      We report a study of the process e⁺e⁻ → (D*D̅*)⁰ π⁰ using e⁺e⁻ collision data samples with integrated luminosities of 1092 pb⁻¹ at √s̅ = 4.23 GeV and 826 pb⁻¹ at √s̅ = 4.26 GeV collected with the BESIII detector at the ...
    • Observation of a Neutral Structure Near the DD̅* Mass Threshold in e⁺e⁻ → (DD̅*)⁰π⁰ at √s= 4.226 and 4.257 GeV 

      Ablikim, M.; Achasov, M. N.; Ai, X. C.; Albayrak, O.; Albrecht, M.; Ambrose, D. J.; Amoroso, A.; Lou, Xinchou; BESII Collaboration (Amer Physical Soc, 2015-11)
      A neutral structure in the DD̅* system around the DD̅* mass threshold is observed with a statistical significance greater than 10σ in the processes e⁺e⁻ → D⁺D*π° + c.c. and e⁺e⁻ →D°D̅*⁰ + c.c. At √s = 4.226 and 4.257 GeV ...
    • Observation of an Excited B_c ^{±} Meson State with the ATLAS Detector 

      Aad, G.; Abbott, B.; Abdallah, J.; Abdel Khalek, S.; Abdinov, O.; Aben, R.; Abi, B.; Izen, Joseph M.; Leyton, Michael; Lou, Xinchou; Namasivayam, Harisankar; Reeves, Kendall; ATLAS Collaboration (American Physical Society, 2014-11-21)
      A search for excited states of theB(±)(c) meson is performed using 4.9 fb⁻¹ of 7 TeV and 19.2 fb⁻¹ of 8 TeV pp collision data collected by the ATLAS experiment at the LHC. A new state is observed through its hadronic ...
    • Observation of B̅ → D* π⁺π⁻ℓ⁻ν̅ Decays in e⁺e⁻ Collisions at the ϒ(4s) Resonance 

      Lees, J. P.; Poireau, V.; Tisserand, V.; Grauges, E.; Palano, A.; Eigen, G.; Stugu, B.; Izen, Joseph M.; Lou, Xinchou; BaBar Collaboration (Amer Physical Soc, 2016-01-26)
      We report on measurements of the decays of B̅ mesons into the semileptonic final states B̅ → D^{(*)} π⁺π⁻ℓ⁻ν̅, where D^{(*())} represents a D or D* meson and ℓ⁻ is an electron or a muon. These measurements are based on 471 ...
    • Observation of e⁺e⁻ → γX(3872) at BESIII 

      Ablikim, M.; Achasov, M. N.; Ai, X. C.; Albayrak, O.; Ambrose, D. J.; An, F. F.; An, Q.; Lou, Xinchou (2014-03-03)
      With data samples collected with the BESIII detector operating at the BEPCII storage ring at center-of-mass energies from 4.009 to 4.420 GeV, the process e⁺e⁻ → γ X(3872) is observed for the first time with a statistical ...
    • Observation of e⁺e⁻ → π⁰π⁰h_c and a Neutral Charmoniumlike Structure Z_c(4020)° 

      Ablikim, M.; Achasov, M. N.; Ai, X. C.; Albayrak, O.; Albrecht, M.; Ambrose, D. J.; Amoroso, A.; Lou, Xinchou; BESIII Collaboration (American Physical Society, 2014-11-18)
      Using data collected with the BESIII detector operating at the Beijing Electron Positron Collider at center-of-mass energies of √s = 4.23, 4.26, and 4.36 GeV, we observe e⁺e⁻ → π⁰π⁰h_c for the first time. The Born cross ...
    • Observation of e⁺e⁻ → ωχ_{c1, 2} near √s̅ = 4.42 and 4.6 GeV 

      Ablikim, M.; Achasov, M. N.; Ai, X. C.; Albayrak, O.; Albrecht, M.; Ambrose, D. J.; Amoroso, A.; Lou, Xinchou; BESIII Collaboration (American Physical Society, 2016-01-14)
      Based on data samples collected with the BESIII detector operating at the BEPCII storage ring at center-of-mass energies √s̅ > 4.4 GeV, the processes e⁺e⁻ → ωχ(c1,2) are observed for the first time. With an integrated ...
    • Observation of J/ψ → pp̅α₀(980) at BESII 

      Ablikim, M.; Achasov, M. N.; Ai, X. C.; Albayrak, O.; Albrecht, M.; Ambrose, D. J.; An, F. F.; Lou, Xinchou (2014-09-26)
      Using 2.25 x 10⁸ J/ψ events collected with the BESIII detector at the BEPCII storage rings, we observe for the first time the process J/ψ → pp̅α₀(980), α₀ → π⁰η with a significance of 6.5σ (3.2σ including systematic ...
    • Observation of Spin Correlation in tt̄ Events from pp Collisions at √s = 7 TeV Using the ATLAS Detector 

      Aad, G.; Abbott, B.; Abdallah, J.; Abdel Khalek, S.; Abdelalim, A. A.; Abdesselam, A.; Abdinov, O.; Ahsan, Mahsana; Izen, Joseph M.; Lou, Xinchou; Reeves, Kendall; Wong, Wei-Cheng; ATLAS Collaboration (American Physical Society, 2012-05-24)
      A measurement of spin correlation in tt̅ production is reported using data collected with the ATLAS detector at the LHC, corresponding to an integrated luminosity of 2.1 fb⁻¹. Candidate events are selected in the dilepton ...
    • Observation of the Decay Λ_c⁺→ Σ⁻π⁺π⁺π⁰ 

      Ablikim, M.; Achasov, M. N.; Ahmed, S.; Albrecht, M.; Amoroso, A.; An, F. F.; An, Q.; Lou, Xinchou (Elsevier B.V, 2017)
      We report the first observation of the decay Λ_c⁺→ Σ⁻π⁺π⁺π⁰, based on data obtained in e⁺e⁻ annihilations with an integrated luminosity of 567 pb⁻¹ at √s̅=4.6 GeV. The data were collected with the BESIII detector at the ...
    • Observation of the Helicity-Selection-Rule Suppressed Decay of the χ(c2) Charmonium State 

      Ablikim, M.; Achasov, M. N.; Ahmed, S.; Ai, X. C.; Albayrak, O.; Albrecht, M.; Ambrose, D. J.; Lou, Xinchou; BESIII Collaboration (Amer Physical Soc, 2018-10-01)
      The decays of χ(c2) → K⁺K⁻ π⁰, K(S)K(±)π(∓), and π⁺π⁻π⁰ are studied with the ψ(3686) data samples collected with the Beijing Spectrometer ( BESIII). For the first time, the branching fractions of χ(c2) → K*K̅, χ(c2) → ...
    • Observation of the Isospin-Violating Decay J/ψ → φπ⁰ f₀(980) 

      Ablikim, M.; Achasov, M. N.; Ai, X. C.; Albayrak, O.; Albrecht, M.; Ambrose, D. J.; Amoroso, A.; Lou, Xinchou; BESIII Collaboration (Amer Physical Soc, 2015-07)
      Using a sample of 1.31 x 10⁹ J/ψ events collected with the BESIII detector at the BEPCII collider, the decays J/ψ → φπ⁺π⁻π⁰ and J/ψ → φπ⁰π⁰π⁰ are investigated. The isospin-violating decay J/ψ → φπ⁰f₀(980) with f₀(980) → ...
    • Observation of the Singly Cabibbo-Suppressed Decay D⁺ → ωπ⁺ and Evidence for D⁰ → ωπ⁰ 

      Ablikim, M.; Achasov, M. N.; Ai, X. C.; Albayrak, O.; Albrecht, M.; Ambrose, D. J.; Amoroso, A.; Lou, Xinchou; BESIII Collaboration (American Physical Society, 2016-02-23)
      Based on 2.93 fb⁻¹ e⁺e⁻ collision data taken at center-of-mass energy of 3.773 GeV by the BESIII detector, we report searches for the singly Cabibbo-suppressed decays D⁺ → ωπ⁺ and D⁰ → ωπ⁰. A double tag technique is used ...
    • Observation of Time-Reversal Violation in the B⁰ Meson System 

      Lees, J. P.; Poireau, V.; Tisserand, V.; Grauges, E.; Palano, A.; Eigen, G.; Izen, Joseph M.; Lou, Xinchou; BaBar Collaboration (American Physical Society, 2012-11-19)
      Although CP violation in the B meson system has been well established by the B factories, there has been no direct observation of time-reversal violation. The decays of entangled neutral B mesons into definite flavor states ...
    • Observation of Top-Quark Pair Production in Association with a Photon and Measurement of the tt̅γ Production Cross Section in pp Collisions at √s=7 TeV Using the ATLAS Detector 

      Aad, G.; Abbott, B.; Abdallah, J.; Abdel Khalek, S.; Abdinov, O.; Aben, R.; Abi, B.; Izen, Joseph M.; Leyton, Michael; Lou, Xinchou; Namasivayam, Harisankar; Reeves, Kendall; ATLAS Collaboration (Amer Physical Soc, 2015-04-01)
      A search is performed for top-quark pairs tt̅ produced together with a photon (γ) with transverse energy greater than 20 GeV using a sample of tt̅ candidate events in final states with jets, missing transverse momentum, ...
    • Observation of Z_c (3900)⁰ in e⁺e⁻ → π⁰π⁰J/ψ 

      Ablikim, M.; Achasov, M. N.; Ai, X. C.; Albayrak, O.; Albrecht, M.; Ambrose, D. J.; Amoroso, A.; Lou, Xinchou; BESIII Collaboration (2015-09-11)
      Using a data sample collected with the BESIII detector operating at the BEPCII storage ring, we observe a new neutral state Z_c (3900)⁰ with a significance of 10.4σ. The mass and width are measured to be 3894.8 ± 2.3 ± 3.2 ...
    • Observation of η'→π⁺π⁻π⁺π⁻ and η'→π⁺π⁻π⁰π⁰ 

      Ablikim, M.; Achasov, M. N.; Ai, X. C.; Albayrak, O.; Albrecht, M.; Ambrose, D. J.; An, F. F.; Lou, Xinchou (2014-06-25)
      Using a sample of 1.3 x 10⁹ J/ψ events collected with the BESIII detector, we report the first observation of η'→π⁺π⁻π⁺π⁻ and η'→π⁺π⁻π⁰π⁰. The measured branching fractions are ℬ(η'→π⁺π⁻π⁺π⁻) = [8.53 ± 0.69(stat.) ± ...
    • Observation of η′ → ωe⁺e⁻ 

      Ablikim, M.; Achasov, M. N.; Ai, X. C.; Albayrak, O.; Albrecht, M.; Ambrose, D. J.; Amoroso, A.; Lou, Xinchou; BESIII Collaboration (Amer Physical Soc, 2015-09-15)
      Based on a sample of η′ mesons produced in the radiative decay J/ψ → γη′ in 1.31 x 10⁹ J/ψ events collected with the BESIII detector, the decay η′ → ωe⁺e⁻ is observed for the first time, with a statistical significance of ...