Measurement of the top quark mass in pp̄ collisions at s=1.96TeV using the decay length technique
Physical Review D - Particles, Fields, Gravitation and Cosmology 75:7 (2007)
Abstract:
We report the first measurement of the top quark mass using the decay length technique in pp̄ collisions at a center-of-mass energy of 1.96 TeV. This technique uses the measured flight distance of the b hadron to infer the mass of the top quark in lepton plus jets events with missing transverse energy. It relies solely on tracking and avoids the jet energy scale uncertainty that is common to all other methods used so far. We apply our novel method to a 695pb-1 data sample recorded by the CDF II detector at Fermilab and extract a measurement of mt=180.7-13.4+15.5(stat.)±8.6(syst.)GeV/c2. While the uncertainty of this result is larger than that of other measurements, the dominant uncertainties in the decay length technique are uncorrelated with those in other methods. This result can help reduce the overall uncertainty when combined with other existing measurements of the top quark mass. © 2007 The American Physical Society.Measurement of the top-quark mass in all-hadronic decays in pp collisions at CDF II.
Phys Rev Lett 98:14 (2007) 142001
Abstract:
We present a measurement of the top-quark mass Mtop in the all-hadronic decay channel tt-->W+bW-b-->q1q2bq3q4b. The analysis is performed using 310 pb-1 of sqrt[s]=1.96 TeV pp[over ] collisions collected with the CDF II detector using a multijet trigger. The mass measurement is based on an event-by-event likelihood which depends on both the sample purity and the value of the top-quark mass, using 90 possible jet-to-parton assignments in the six-jet final state. The joint likelihood of 290 selected events yields a value of Mtop=177.1+/-4.9(stat)+/-4.7(syst) GeV/c2.Search for single production of scalar leptoquarks in p over(p, ̄) collisions decaying into muons and quarks with the D0 detector
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 647:2-3 (2007) 74-81
Abstract:
We report on a search for second generation leptoquarks (LQ2) which decay into a muon plus quark in p over(p, ̄) collisions at a center-of-mass energy of sqrt(s) = 1.96 TeV in the D0 detector using an integrated luminosity of about 300 pb-1. No evidence for a leptoquark signal is observed and an upper bound on the product of the cross section for single leptoquark production times branching fraction β into a quark and a muon was determined for second generation scalar leptoquarks as a function of the leptoquark mass. This result has been combined with a previously published D0 search for leptoquark pair production to obtain leptoquark mass limits as a function of the leptoquark-muon-quark coupling, λ. Assuming λ = 1, lower limits on the mass of a second generation scalar leptoquark coupling to a u quark and a muon are mLQ2 > 274 GeV and mLQ2 > 226 GeV for β = 1 and β = 1 / 2, respectively. © 2007 Elsevier B.V. All rights reserved.Measurement of the top-quark mass in all-hadronic decays in pp̄ collisions at CDF II
Physical Review Letters 98:14 (2007)
Abstract:
We present a measurement of the top-quark mass Mtop in the all-hadronic decay channel tt̄→W+bW-b̄→q1q̄2bq3q̄4b̄. The analysis is performed using 310pb-1 of s=1.96TeV pp̄ collisions collected with the CDF II detector using a multijet trigger. The mass measurement is based on an event-by-event likelihood which depends on both the sample purity and the value of the top-quark mass, using 90 possible jet-to-parton assignments in the six-jet final state. The joint likelihood of 290 selected events yields a value of Mtop=177.1±4.9(stat)±4.7(syst)GeV/c2. © 2007 The American Physical Society.Analysis of the quantum numbers J(PC) of the X(3872) particle.
Phys Rev Lett 98:13 (2007) 132002