Showing papers by "Brad Abbott published in 1995"
TL;DR: In this article, the search for the top quark in p anti-p collisions at S**(1/2) = 1.8 TeV with an integrated luminosity of 13.9.
Abstract: We present new results on the search for the top quark in p anti-p collisions at S**(1/2) = 1.8 TeV with an integrated luminosity of 13.5 +- 1.6 pb**(-1). We have considered t anti-t production in the Standard Model using electron and muon dilepton decay channels (t anti-t -> e mu + jets, e e + jets, and mu mu + jets) and single-lepton decay channels (t anti-t -> e + jets and mu + jets) with and without tagging of b quark jets. From all channels, we have 9 events with an expected background of 3.8 +- 0.9. If we assume that the excess is due to t anti-t production, and assuming a top mass of 180 GeV/c**2, we obtain a cross section of 8.2 +- 5.1 pb.
151 citations
TL;DR: In this article, a search for events consistent with the production and decay of the squarks and gluinos of the minimal supersymmetric standard model (MSSM) in the D0 detector at the Fermilab Tevatron {ital p{bar p}} collider was presented.
Abstract: We present a search for events consistent with the production and decay of the squarks and gluinos of the minimal supersymmetric standard model (MSSM) in the D0 detector at the Fermilab Tevatron {ital p{bar p}} collider. We examined data for events containing large missing transverse energy and three or more jets. We observed no excess of events above the expected yield from standard model processes. For a choice of MSSM parameter values, we set a lower limit at the 95% confidence level on the mass of the gluino of 144 GeV/{ital c}{sup 2} for all squark masses and a lower limit of 212 GeV/{ital c}{sup 2} for equal squark and gluino masses.
106 citations
TL;DR: The inclusive muon spectrum extends over the kinematic range {vert_bar}{ital y}{Sup {mu}}{vert-bar}{lt}0.8 and 3.5{lt}{ital p}{sub {ital T}}{sup {mu}60GeV/{ital c}, and is well described by the expected contributions from various known sources.
Abstract: We report a measurement of the inclusive muon and {ital b}-quark production cross sections in {ital p{bar p}} collisions at {radical}{ital s}=1.8 TeV using the D0 detector at the Fermilab Tevatron collider. The inclusive muon spectrum extends over the kinematic range {vert_bar}{ital y}{sup {mu}}{vert_bar}{lt}0.8 and 3.5{lt}{ital p}{sub {ital T}}{sup {mu}}{lt}60GeV/{ital c}, and is well described by the expected contributions from various known sources. The {ital b}-quark production cross section for {vert_bar}{ital y}{sup {ital b}}{vert_bar}{lt}1.0 and {ital p}{sup {ital b}}{sub {ital T}}{gt}6GeV/{ital c} is extracted, and agrees with next-to-leading order QCD predictions within the experimental and theoretical uncertainties.
84 citations
TL;DR: In this paper, the W boson mass in W − ev decays was measured using 1 fb^-1 of data collected with the D0 detector during Run II of the Fermilab Tevatron collider.
Abstract: We present a measurement of the W boson mass in W -> ev decays using 1 fb^-1 of data collected with the D0 detector during Run II of the Fermilab Tevatron collider. With a sample of 499830 W -> ev candidate events, we measure M_W = 80.401 +- 0.043 GeV. This is the most precise measurement from a single experiment.
75 citations
TL;DR: Results on the search for the top quark in {ital p{bar p}} collisions at {radical}{ital s} =1.8 TeV with an integrated luminosity of 13.5 TeV are presented.
Abstract: We present results on the search for the top quark in {ital p{bar p}} collisions at {radical}{ital s} =1.8 TeV with an integrated luminosity of 13.5{plus_minus}1.6 pb{sup {minus}1}. We have considered {ital t{bar t}} production in the standard model using electron and muon dilepton decay channels ({ital t{bar t}}{r_arrow}{ital e}{mu}+jets, {ital ee}+jets, and {mu}{mu}+jets) and single-lepton decay channels ({ital t{bar t}}{r_arrow}{ital e}+jets and {mu}+jets) with and without tagging of {ital b} quark jets. An analysis of these data optimized for top quark masses below 140 GeV/{ital c}{sup 2} gives a lower top quark mass limit of 128 GeV/{ital c}{sup 2}. An analysis optimized for higher top quark masses yields 9 events with an expected background of 3.8{plus_minus}0.9. If we assume that the excess is due to {ital t{bar t}} production, and assuming a top quark mass of 180 GeV/{ital c}{sup 2}, we obtain a cross section of 8.2{plus_minus}5.1 pb.
55 citations
TL;DR: In this article, the authors measured the transverse energy in jets in p p collisions at s = 1.8 TeV TeV using the DO detector at Fermilab.
35 citations
TL;DR: In this article, the authors measured the cross section times leptonic branching ratios for the Fermilab Tevatron collider at the D0 detector at the FERILAB Tevaton collider.
Abstract: The inclusive cross sections times leptonic branching ratios for $W$ and $Z$ boson production in $p\overline{p}$ collisions at $\sqrt{s}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1.8$ TeV were measured using the D0 detector at the Fermilab Tevatron collider: ${\ensuremath{\sigma}}_{W}B(W\ensuremath{\rightarrow}e\ensuremath{
u})\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}2.36\ifmmode\pm\else\textpm\fi{}0.07\ifmmode\pm\else\textpm\fi{}0.13\mathrm{nb}$, ${\ensuremath{\sigma}}_{W}B\left(W\ensuremath{\rightarrow}\ensuremath{\mu}\ensuremath{
u}\right)\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}2.09\ifmmode\pm\else\textpm\fi{}0.23\ifmmode\pm\else\textpm\fi{}0.11\mathrm{nb}$, ${\ensuremath{\sigma}}_{Z}B\left(Z\ensuremath{\rightarrow}{e}^{+}{e}^{\ensuremath{-}}\right)\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0.218\ifmmode\pm\else\textpm\fi{}0.011\ifmmode\pm\else\textpm\fi{}0.012\mathrm{nb}$, and ${\ensuremath{\sigma}}_{Z}B\left(Z\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}\right)\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0.178\ifmmode\pm\else\textpm\fi{}0.030\ifmmode\pm\else\textpm\fi{}0.009\mathrm{nb}$. The first error is the combined statistical and systematic uncertainty, and the second reflects the uncertainty in the luminosity. For the combined electron and muon analyses we find ${\ensuremath{\sigma}}_{W}B(W\ensuremath{\rightarrow}l\ensuremath{
u})/{\ensuremath{\sigma}}_{Z}B(Z\ensuremath{\rightarrow}{l}^{+}{l}^{\ensuremath{-}})\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}10.90\ifmmode\pm\else\textpm\fi{}0.49$. Assuming standard model couplings, this result is used to determine the width of the $W$ boson, $\ensuremath{\gamma}(W)\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}2.044\ifmmode\pm\else\textpm\fi{}0.093\mathrm{GeV}$.
34 citations
TL;DR: In this paper, the authors measured the gauge boson couplings using $p\bar{p}to \ell
u\gamma+X$ ($\ell=e,\mu$) events at $\sqrt{s}=1.8$ TeV observed with the Fermilab Tevatron Collider.
Abstract: The $WW\gamma$ gauge boson couplings were measured using $p\bar{p}\to \ell
u\gamma+X$ ($\ell=e,\mu$) events at $\sqrt{s}=1.8$ TeV observed with the {D\O} detector at the Fermilab Tevatron Collider. The signal, obtained from the data corresponding to an integrated luminosity of $13.8 {\rm pb}^{-1}$, agrees well with the Standard Model prediction. A fit to the photon transverse energy spectrum yields limits at the 95% confidence level on the CP--conserving anomalous coupling parameters of $-1.6<\Delta\kappa<1.8$ ($\lambda$ = 0) and $-0.6<\lambda<0.6$ ($\Delta\kappa$ = 0).
25 citations
TL;DR: In this article, the results of a search for W boson pair production in p{bar p} collisions at {radical}s = 1.8 TeV with subsequent decay to dilepton (e{mu, ee, and {mu}{mu}) channels are presented.
Abstract: The results of a search for W boson pair production in p{bar p} collisions at {radical}s = 1.8 TeV with subsequent decay to dilepton (e{mu}, ee, and {mu}{mu}) channels are presented. One event is observed with an expected background of 0.56 {plus_minus} 0.13 events with an integrated luminosity of approximately 14 pb{sup {minus}1}. Assuming equal strengths for the WWZ and WW{gamma} gauge boson coupling parameters {kappa} and {lambda}, limits on the CP-conserving anomalous coupling constants are {minus}2.6 < {delta}{kappa} < 2.8 and {minus}2.1 {lambda} < 2.1 at the 95% confidence level.
22 citations
TL;DR: In this article, the authors measured the ratio of the number of {ital W}+1 jet to {ital E}+0 jet events with the D0 detector using data from the 1992--93 Tevatron Collider run.
Abstract: The ratio of the number of {ital W}+1 jet to {ital W}+0 jet events is measured with the D0 detector using data from the 1992--93 Tevatron Collider run. For the {ital W}{r_arrow}{ital e}{nu} channel with a minimum jet {ital E}{sub {ital T}} cutoff of 25 GeV, the experimental ratio is 0.065{plus_minus}0.003(stat){plus_minus}0.007(syst). Next-to-leading order QCD predictions for various parton distributions agree well with each other and are all over 1 standard deviation below the measurement. Varying the strong coupling constant {alpha}{sub {ital s}} in both the parton distributions and the partonic cross sections simultaneously does not remove this discrepancy. {copyright} {ital 1995} {ital The} {ital American} {ital Physical} {ital Society}.
19 citations
TL;DR: In this article, the authors used the photon transverse energy spectrum (PES) model to fit the δ-1.6-kappa-conserving anomalous coupling parameters of {minus} 1.6{lt δ 1.8 ({lambda}=0) and δ 0.6
Abstract: The {ital WW}{gamma} gauge boson couplings were measured using {ital p{bar p}}{r_arrow}l{nu}{gamma}+{ital X} (l={ital e},{mu}) events at {radical}{ital s}=1.8 TeV observed with the D0 detector at the Fermilab Tevatron Collider. The signal, obtained from the data corresponding to an integrated luminosity of 13.8pb{sup {minus}1}, agrees well with the standard model prediction. A fit to the photon transverse energy spectrum yields limits at the 95% confidence level on the {ital CP}-conserving anomalous coupling parameters of {minus}1.6{lt}{Delta}{kappa}{lt}1.8 ({lambda}=0) and {minus}0.6{lt}{lambda}{lt}0.6 ({Delta}{kappa}=0). Similar limits are obtained for the {ital CP}-violating coupling parameters.
TL;DR: In this paper, the authors performed a direct search for the anomalous {ital ZZ}{gamma} and ε-Gamma-gamma couplings by studying {ital p{bar p}{r_arrow}ll{gamma+{ital X} (l={ital e},{mu}) events at 1.8 TeV with the D0 detector at the Fermilab Tevatron Collider.
Abstract: We performed a direct search for the anomalous {ital ZZ}{gamma} and {ital Z}{gamma}{gamma} couplings by studying {ital p{bar p}}{r_arrow}ll{gamma}+{ital X} (l={ital e},{mu}) events at {radical}{ital s}=1.8 TeV with the D0 detector at the Fermilab Tevatron Collider. A fit to the transverse energy spectrum of the photon in the signal events, based on the data set corresponding to an integrated luminosity of 14.3pb{sup {minus}1} (13.7pb{sup {minus}1}) for the electron (muon) channel, yields the following 95% confidence level limits on the anomalous {ital CP}-conserving {ital ZZ}{gamma} couplings: {vert_bar}{ital h}{sub 30}{sup {ital Z}}{vert_bar}{lt}1.8 ({ital h}{sub 40}{sup {ital Z}}=0) and {vert_bar}{ital h}{sub 40}{sup {ital Z}}{vert_bar}{lt}0.5 ({ital h}{sub 30}{sup {ital Z}}=0), for a form-factor scale {Lambda}=500 GeV. Limits for the {ital Z}{gamma}{gamma} couplings and {ital CP}-violating couplings are also discussed.
TL;DR: In this paper, a search for second generation scalar leptoquarks with the D0 detector at the Fermilab Tevatron pp collider at √s = 1.8 TeV is reported.
Abstract: We report on a search for second generation scalar leptoquarks with the D0 detector at the Fermilab Tevatron pp collider at √s = 1.8 TeV. This search is based on 12.7 pb-1 of data. Second generation leptoquarks are assumed to be produced in pairs and to decay into a neutrino and quark with branching ratio β or into a neutrino and quark with branching ratio 1 - β. We obtain cross section times branching ratio limits as a function of leptoquark mass and set lower limits on the leptoquark mass at the 95% confidence level.
TL;DR: In this article, a search for a heavy charged gauge boson, W′, using the decay channels W′ → eν and W´ → τν → e´νν ν is reported.
01 Jan 1995
TL;DR: In this paper, the authors present a survey of the state-of-the-art work in the field of computer vision and its application in the context of cyber-physical learning.
Abstract: S. Abachi,12 B. Abbott,34 M. Abolins,23 B. S. Acharya,42 I. Adam,10 D. L. Adams,35 M. Adams,15 S. Ahn,12 H. Aihara,20 J. Alitti,38 G. Alvarez,16 G. A. Alves,8 E. Amidi,27 N. Amos,22 E. W. Anderson,17 S. H. Aronson,3 R. Astur,40 R. E. Avery,29 A. Baden,21 V. Balamurali,30 J. Balderston,14 B. Baldin,12 J. Bantly,4 J. F. Bartlett,12 K. Bazizi,37 J. Bendich,20 S. B. Beri,32 I. Bertram,35 V. A. Bezzubov,33 P. C. Bhat,12 V. Bhatnagar,32 M. Bhattacharjee,11 A. Bischoff,7 N. Biswas,30 G. Blazey,12 S. Blessing,13 P. Bloom,5 A. Boehnlein,12 N. I. Bojko,33 F. Borcherding,12 J. Borders,37 C. Boswell,7 A. Brandt,12 R. Brock,23 A. Bross,12 D. Buchholz,29 V. S. Burtovoi,33 J. M. Butler,12 W. Carvalho,8 D. Casey,37 H. Castilla-Valdez,9 D. Chakraborty,40 S.-M. Chang,27 S. V. Chekulaev,33 L.-P. Chen,20 W. Chen,40 L. Chevalier,38 S. Chopra,32 B. C. Choudhary,7 J. H. Christenson,12 M. Chung,15 D. Claes,40 A. R. Clark,20 W. G. Cobau,21 J. Cochran,7 W. E. Cooper,12 C. Cretsinger,37 D. Cullen-Vidal,4 M. A. C. Cummings,14 D. Cutts,4 O. I. Dahl,20 K. De,43 M. Demarteau,12 R. Demina,27 K. Denisenko,12 N. Denisenko,12 D. Denisov,12 S. P. Denisov,33 W. Dharmaratna,13 H. T. Diehl,12 M. Diesburg,12 G. Di Loreto,23 R. Dixon,12 P. Draper,43 J. Drinkard,6 Y. Ducros,38 S. R. Dugad,42 S. Durston-Johnson,37 D. Edmunds,23 J. Ellison,7 V. D. Elvira,12,* R. Engelmann,40 S. Eno,21 G. Eppley,35 P. Ermolov,24 O. V. Eroshin,33 V. N. Evdokimov,33 S. Fahey,23 T. Fahland,4 M. Fatyga,3 M. K. Fatyga,37 J. Featherly,3 S. Feher,40 D. Fein,2 T. Ferbel,37 G. Finocchiaro,40 H. E. Fisk,12 Y. Fisyak,5 E. Flattum,23 G. E. Forden,2 M. Fortner,28 K. C. Frame,23 P. Franzini,10 S. Fuess,12 E. Gallas,43 A. N. Galyaev,33 S. G. Gao,12,† T. L. Geld,23 R. J. Genik II,23 K. Genser,12 C. E. Gerber,12,‡ B. Gibbard,3 V. Glebov,37 S. Glenn,5 B. Gobbi,29 M. Goforth,13 A. Goldschmidt,20 B. Gomez,1 P. I. Goncharov,33 J. L. Gonzalez Solis,9 H. Gordon,3 L. T. Goss,44 N. Graf,3 P. D. Grannis,40 D. R. Green,12 J. Green,28 H. Greenlee,12 G. Griffin,6 N. Grossman,12 P. Grudberg,20 S. Grunendahl,37 W. X. Gu,12,† G. Guglielmo,31 J. A. Guida,40 J. M. Guida,3 W. Guryn,3 S. N. Gurzhiev,33 P. Gutierrez,31 Y. E. Gutnikov,33 N. J. Hadley,21 H. Haggerty,12 S. Hagopian,13 V. Hagopian,13 K. S. Hahn,37 R. E. Hall,6 S. Hansen,12 R. Hatcher,23 J. M. Hauptman,17 D. Hedin,28 A. P. Heinson,7 U. Heintz,12 R. Hernandez-Montoya,9 T. Heuring,13 R. Hirosky,13 J. D. Hobbs,12 B. Hoeneisen,1, J. S. Hoftun,4 F. Hsieh,22 Tao Hu,12, Ting Hu,40 Tong Hu,16 T. Huehn,7 S. Igarashi,12 A. S. Ito,12 E. James,2 J. Jaques,30 S. A. Jerger,23 J. Z.-Y. Jiang,40 T. Joffe-Minor,29 H. Johari,27 K. Johns,2 M. Johnson,12 H. Johnstad,41 A. Jonckheere,12 M. Jones,14 H. Jostlein,12 S. Y. Jun,29 C. K. Jung,40 S. Kahn,3 G. Kalbfleisch,31 J. S. Kang,18 R. Kehoe,30 M. L. Kelly,30 A. Kernan,7 L. Kerth,20 C. L. Kim,18 S. K. Kim,39 A. Klatchko,13 B. Klima,12 B. I. Klochkov,33 C. Klopfenstein,5 V. I. Klyukhin,33 V. I. Kochetkov,33 J. M. Kohli,32 D. Koltick,34 A. V. Kostritskiy,33 J. Kotcher,3 J. Kourlas,26 A. V. Kozelov,33 E. A. Kozlovski,33 M. R. Krishnaswamy,42 S. Krzywdzinski,12 S. Kunori,21 S. Lami,40 G. Landsberg,12 J-F. Lebrat,38 A. Leflat,24 H. Li,40 J. Li,43 Y. K. Li,29 Q. Z. Li-Demarteau,12 J. G. R. Lima,36 D. Lincoln,22 S. L. Linn,13 J. Linnemann,23 R. Lipton,12 Y. C. Liu,29 F. Lobkowicz,37 S. C. Loken,20 S. Lokos,40 L. Lueking,12 A. L. Lyon,21 A. K. A. Maciel,8 R. J. Madaras,20 R. Madden,13 I. V. Mandrichenko,33 Ph. Mangeot,38 S. Mani,5 B. Mansoulie,38 H. S. Mao,12,† S. Margulies,15 R. Markeloff,28 L. Markosky,2 T. Marshall,16 M. I. Martin,12 M. Marx,40 B. May,29 A. A. Mayorov,33 R. McCarthy,40 T. McKibben,15 J. McKinley,23 T. McMahon,31 H. L. Melanson,12 J. R. T. de Mello Neto,36 K. W. Merritt,12 H. Miettinen,35 A. Milder,2 A. Mincer,26 J. M. de Miranda,8 C. S. Mishra,12 M. Mohammadi-Baarmand,40 N. Mokhov,12 N. K. Mondal,42 H. E. Montgomery,12 P. Mooney,1 M. Mudan,26 C. Murphy,16 C. T. Murphy,12 F. Nang,4 M. Narain,12 V. S. Narasimham,42 A. Narayanan,2 H. A. Neal,22 J. P. Negret,1 E. Neis,22 P. Nemethy,26 D. Nesic,4 M. Nicola,8 D. Norman,44 L. Oesch,22 V. Oguri,36 E. Oltman,20 N. Oshima,12 D. Owen,23 P. Padley,35 M. Pang,17 A. Para,12 C. H. Park,12 Y. M. Park,19 R. Partridge,4 N. Parua,42 M. Paterno,37 J. Perkins,43 A. Peryshkin,12 M. Peters,14 H. Piekarz,13 Y. Pischalnikov,34 A. Pluquet,38 V. M. Podstavkov,33 B. G. Pope,23 H. B. Prosper,13 S. Protopopescu,3 D. Puseljic,20 J. Qian,22 P. Z. Quintas,12 R. Raja,12 S. Rajagopalan,40 O. Ramirez,15 M. V. S. Rao,42 P. A. Rapidis,12 L. Rasmussen,40 A. L. Read,12 S. Reucroft,27 M. Rijssenbeek,40 T. Rockwell,23 N. A. Roe,20 P. Rubinov,40 R. Ruchti,30 S. Rusin,24 J. Rutherfoord,2 A. Santoro,8 L. Sawyer,43 R. D. Schamberger,40 H. Schellman,29 J. Sculli,26 E. Shabalina,24 C. Shaffer,13 H. C. Shankar,42 Y. Y. Shao,12,† R. K. Shivpuri,11 M. Shupe,2 J. B. Singh,32 V. Sirotenko,28 W. Smart,12 A. Smith,2 R. P. Smith,12 R. Snihur,29 G. R. Snow,25 S. Snyder,40 J. Solomon,15 P. M. Sood,32 M. Sosebee,43 M. Souza,8 A. L. Spadafora,20 R. W. Stephens,43 M. L. Stevenson,20 D. Stewart,22 D. A. Stoianova,33 D. Stoker,6 K. Streets,26 M. Strovink,20 A. Sznajder,8 A. Taketani,12 P. Tamburello,21 J. Tarazi,6 M. Tartaglia,12 T. L. Taylor,29 J. Teiger,38 J. Thompson,21 T. G. Trippe,20 P. M. Tuts,10 N. Varelas,23 E. W. Varnes,20 P. R. G. Virador,20 D. Vititoe,2 A. A. Volkov,33