Showing papers by "Brad Abbott published in 1994"
TL;DR: A lower limit on the top quark mass is obtained of 131 GeV/[ital c][sup 2] at the 95% confidence level, assuming standard model branching fractions and a predicted cross section for [ital t[bar t]] production.
Abstract: We have searched for evidence of top quark production in pp\ifmmode\bar\else\textasciimacron\fi{} collisions at \ensuremath{\surd}s =1.8 TeV using the D0 detector at the Fermilab Tevatron collider. For an integrated luminosity of 15 ${\mathrm{pb}}^{\mathrm{\ensuremath{-}}1}$, we report results of a search for tt\ifmmode\bar\else\textasciimacron\fi{} pairs in the decay modes tt\ifmmode\bar\else\textasciimacron\fi{}\ensuremath{\rightarrow}e\ensuremath{\mu}+jets,ee+jets,e+jets, and \ensuremath{\mu}+jets. From analyses of these modes we obtain a lower limit on the top quark mass of 131 GeV/${\mathit{c}}^{2}$ at the 95% confidence level, assuming standard model branching fractions and a predicted cross section for tt\ifmmode\bar\else\textasciimacron\fi{} production. We discuss the properties of an event for which expected backgrounds are small.
72 citations
TL;DR: It is reported on a search for first generation leptoquarks with the DO detector at the Fermilab Tevatron [ital p[bar p]] collider at [radical][ital s] =1.8 TeV, and cross section times branching ratio limits as a function of leptonoquark mass are obtained.
Abstract: We report on a search for first generation leptoquarks with the DO detector at the Fermilab Tevatron [ital p[bar p]] collider at [radical][ital s] =1.8 TeV. This search is based on 15 pb[sup [minus]1] of data. Leptoquarks are assumed to be produced in pairs and to decay into an electron + quark with branching ratio [beta]. No leptoquark candidates were found. We obtain cross section times branching ratio limits as a function of leptoquark mass. For pair production of scalar leptoquarks, we set a leptoquark mass limit of 133 GeV for [beta]=1 and 120 GeV for [beta]=0.5 at 95% confidence level.
35 citations
01 Feb 1994-Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment
TL;DR: In this article, a 96-channel, 3-superlayer, scintillating-fiber tracking system has been tested in a 5 GeV/ cπ − beam, achieving a spatial resolution of ∼ 150 μm for a double-layered ribbon.
Abstract: A 96-channel, 3-superlayer, scintillating-fiber tracking system has been tested in a 5 GeV/ cπ − beam. The scintillating fibers were 830 μm in diameter, spaced 850 μm apart, and 4.3 m in length. They were coupled to 6 m long, clear fiber waveguides and finally to visible light photon counters. A spatial resolution of ∼ 150 μm for a double-layered ribbon was achieved with this tracking system. This first prototype of a charged-particle tracking system configured for the Solenoidal Detector Collaboration at the Superconducting Super Collider is a benchmark in verifying the expected number of photoelectrons from the fibers.
8 citations