Events with a Rapidity Gap between Jets in p¯p Collisions at √s=630 GeV
Physical Review Letters American Physical Society (APS) 81:24 (1998) 5278-5283
Measurement of three-jet distributions in photoproduction at HERA
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 443:1-4 (1998) 394-408
Abstract:
The cross section for the photoproduction of events containing three jets with a three-jet invariant mass of M31 > 50 GeV has been measured with the ZEUS detector at HERA. The three-jet angular distributions are inconsistent with a uniform population of the available phase space but are well described by parton shower models and script O sign(α α2s) pQCD calculations. Comparisons with the parton shower model indicate a strong contribution from initial state radiation as well as a sensitivity to the effects of colour coherence. © 1998 Elsevier Science B.V. All rights reserved.Observation of Bc mesons in pp̄ collisions at √s = 1.8 TeV
Physical Review D - Particles, Fields, Gravitation and Cosmology 58:11 (1998)
Abstract:
We report the observation of bottom-charmed mesons Bc ni 1.8 TeV pp̄ collisions using the CDF detector at the Fermilab Tevatron. The Bc mesons were found through their semileptonic decays, B±c → J/ψl± X. A fit to the J/ψl mass distribution yielded 20.4+6.2-5.5 events from Bc mesons. A test of the null hypothesis, i.e., an attempt to fit the data with background alone, was rejected at the level of 4.8 standard deviations. By studying the quality of the fit as a function of the assumed Bc mass, we determined M(Bc) = 6.40 ±0.39 (stat.)±0.13 (syst) GeV/c2. From the distribution of trilepton intersection points in the plane transverse to the beam direction we measure the Bc lifetime to be τ(Bc) = 0.46+0.18-0.16 (stat)±0.03 (syst) ps. We also measured the ratio of production cross section times branching fraction for B+c → J/ψl+ v relative to that for B+ → J/ψK+ to be σ(Bc)×B(B c→J/ψlv)/σ(B)×B(B→J/ψK) = 0.132+0.041-0.037 (stat)±0.031 (syst)+0.032-0.020(lifetime).Observation of Bc mesons in pp¯ collisions at s=1.8 TeV
Physical Review D American Physical Society (APS) 58:11 (1998) 112004
Search for Second Generation Leptoquarks in the Dimuon Plus Dijet Channel of pp¯ Collisions at √s=1.8 TeV
Physical Review Letters American Physical Society (APS) 81:22 (1998) 4806-4811