Observation of high momentum η′ production in b decays
Physical Review Letters 81:9 (1998) 1786-1790
Abstract:
We report the first observation of B → η′X transitions with high momentum η′ mesons. We observe 39.0 ± 11.6B decay events with 2.0 < pη′ < 2.7GeV/c, the high momentum region where background from b → c processes is suppressed. We discuss the physical interpretation of the signal, including the possibility that it is due to b → sg* transitions. Given that interpretation, we find B(B → η′Xs) = [6.2 ± 1.6(stat) ± 1.3(syst)+0.0-1.5(bkg)] × 10-4 for 2.0 < pη′ < 2.7GeV/c. © 1998 The American Physical Society.Properties of photon plus two-jet events in p¯p collisions at √s=1.8 TeV
Physical Review D Particles Fields Gravitation and Cosmology 57:1 (1998) 67-77
Abstract:
We present the first general measurements (invariant-mass, transverse-energy, and angular distributions) of the process, (Formula presented) (Formula presented) using data collected by the CDF at Fermilab. We compare the data with predictions from a tree-level QCD calculation and the PYTHIA shower Monte Carlo program. Our data sample is particularly sensitive to contributions from initial- and final-state radiation of photons and jets. Using the PYTHIA Monte Carlo program, we contrast the kinematical distributions for direct photon production with those for initial- and final-state photon radiation (bremsstrahlung). Based on the angular distributions, we find that our data favor a mixture of bremsstrahlung and direct photon production, as predicted, over either process alone. © 1998 The American Physical Society.Search for color-suppressed [Formula presented] hadronic decay processes at the [Formula presented] resonance
Physical Review D - Particles, Fields, Gravitation and Cosmology 57:9 (1998) 5363-5369
Abstract:
Using (Formula presented) of data accumulated at the (Formula presented) by the CLEO-II detector, corresponding to (Formula presented) (Formula presented) pairs, we have searched for the color-suppressed (Formula presented) hadronic decay processes (Formula presented) where (Formula presented) is a light neutral meson (Formula presented) (Formula presented) η, (Formula presented) or ω. The (Formula presented) mesons are reconstructed in (Formula presented) and the (Formula presented) mesons in (Formula presented) (Formula presented) and (Formula presented) decay modes. No obvious signal is observed. We set 90% C.L. upper limits on these modes, varying from (Formula presented) for (Formula presented) to (Formula presented) for (Formula presented). © 1998 The American Physical Society.Search for flavor-changing neutral current decays of the top quark in pp collisions at √s = 1.8 TeV
Physical Review Letters 80:12 (1998) 2525-2530
Abstract:
We search for the flavor-changing neutral current decays of the top quark t → λ and t → qZ (here represents the c and u quarks) in pp collisions at √s = 1.8 TeV. We use a dataset (∫ L dt˜ 110pb-1) collected during the 1992-1995 run of the Collider Detector at Fermilab. We set 95% confidence level limits on the branching fractions B(t → qλ) < 3.2% and B(t → qZ) < 33%, consistent with the standard model. © 1998 The American Physical Society.Search for long-lived parents of Z° bosons inpp collisions at √s = 1.8 TeV
Physical Review D 58:5 (1998)