Direct measurement of the top quark mass by the DØ Collaboration
Physical Review D - Particles, Fields, Gravitation and Cosmology 58:5 (1998)
Abstract:
We determine the top quark mass mt using tt̄ pairs produced in the DØ deteetor by √s = 1.8 TeV pp̄ collisions in a 125 ph-1 exposure at the Fermilab Tevatron. We make a two constraint fit to mt in tt̄→bW+b̄W- final states with one W boson decaying to qq̄ and the other to eν or μν. Likelihood fits to the data yield mt(l+jets) = 173.3±5.6 (stat) ± 5.5 (syst) GeV/c2. When this result is combined with an analysis of events in which both W bosons decay into leptons, we obtain mt = 172.1 ± 5.2 (stat) ± 4.9 (syst) GeV/c2. An alternate analysis, using three constraint fits to fixed top quark masses, gives mt(l + jets) = 176.0 ± 7.9 (stat) ± 4.8 (syst) GeV/c2, consistent with the above result. Studies of kinematic distributions of the top quark candidates are also presented.Limits on WWγ and WWZ couplings from W boson pair production
Physical Review D Particles Fields Gravitation and Cosmology 58:5 (1998) 511011-511016
Abstract:
The results of a search for W boson pair production in pp̄ collisions at √s = 1.8 TeV with subsequent decay to eμ, ee, and μμ channels are presented. Five candidate events are observed with an expected background of 3.1 ± 0.4 events for an integrated luminosity of approximately 97 pb-1. Limits on the anomalous couplings are obtained from a maximum likelihood fit of the EMeasurement of the lepton charge asymmetry in W-boson decays produced in p-pbar collisions
ArXiv hep-ex/9809001 (1998)
Search for long-lived parents of Z0 bosons in pp̄ collisions at √s = 1.8 TeV
Physical Review D - Particles, Fields, Gravitation and Cosmology 58:5 (1998) 511021-511025
Abstract:
We search for new long-lived particles which decay to Z0 bosons by looking tor Z0→e+e- decays with displaced vertices. We find no evidence for parent particles of the Z0 with long lifetimes in 90 pb-1 of data from the CDF experiment at Fermilab. We set a cross section limit as a function of the lifetime of the parent particle for both a generic Z0 parent and a fourth-generation, charge -1/3 quark that decays into Z0b.Search for long-lived parents of Z0 bosons in pp¯ collisions at s=1.8 TeV
Physical Review D American Physical Society (APS) 58:5 (1998) 051102