Exclusive photoproduction of J/ψ mesons at HERA
European Physical Journal C 24:3 (2002) 345-360
Abstract:
The exclusive photoproduction of J/ψ mesons, γp → J/ψp, has been studied in ep collisions with the ZEUS detector at HERA, in the kinematic range 20 < W < 290 GeV, where W is the photon-proton centre-of-mass energy. The J/ψ mesons were reconstructed in the ninon and the electron decay channels using integrated luminosities of 38 pb-1 and 55 pb-1, respectively. The helicity structure of J/ψ production shows that the hypothesis of s-channel helicity conservation is satisfied within two standard deviations. The total cross section and the differential cross-section dσ/dt, where t is the squared four-momentum transfer at the proton vertex, are presented as a function of W, for |t| < 18 Ge2. The t distribution exhibits an exponential shape with a slope parameter increasing logarithmically with W with a value b = 4.15 ± 0.05(stat.)-0.18+0.30(syst.) GeV-2 at W = 90 GeV. The effective parameters of the Pomeron trajectory are αℙ(0) = 1.200 ± 0.009(stat.) -0.010+0.004(Syst.) and α′ℙ = 0.115 ± 0.018(stat.)-0.015+0.008(syst.) GeV-2.Measurement of the B0 lifetime with partially reconstructed B0 → D-ℓ+νℓ decays
Physical Review Letters 89:1 (2002) 118021-118027
Abstract:
The measurement of B0 lifetime with partially reconstructed B0→D-ℓ+νℓ decay was presented. The statistical error of the validation was included in the background systematic error. Results showed that the final relative error of ±1.9% was found by adding in quadrature the uncertainties from the sources.Review of Particle Physics: Particle data group
66:1 I (2002) 100011-10001958
Abstract:
This biennial Review summarizes much of Particle Physics. Using data from previous editions, plus 2205 new measurements from 667 papers, we list, evaluate, and average measured properties of gauge bosons, leptons, quarks, mesons, and baryons. We also summarize searches for hypothetical particles such as Higgs bosons, heavy neutrinos, and supersymmetric particles. All the particle properties and search limits are listed in Summary Tables. We also give numerous tables, figures, formulae, and reviews of topics such as the Standard Model, particle detectors, probability, and statistics. This edition features expanded coverage of CP violation in B mesons and of neutrino oscillations. For the first time we cover searches for evidence of extra dimensions (both in the particle listings and in a new review). Another new review is on Grand Unified Theories. A booklet is available containing the Summary Tables and abbreviated versions of some of the other sections of this full Review. All tables, listings, and reviews (and errata) are also available on the Particle Data Group website: http://pdg.lbl.gov.Search for new physics in photon-lepton events in pp¯ collisions at s=1.8 TeV
Physical Review D American Physical Society (APS) 66:1 (2002) 012004
Search for the rare decays B → Kl+l- and B → K*l+l-
Physical Review Letters 88:24 (2002) 2418011-2418017