Measurement of the Top Quark Mass in P Anti-p Collisions at S**ư

Measurement of the Top Quark Mass in P Anti-p Collisions at S**ư
Author:
Publisher:
Total Pages: 23
Release: 2006
Genre:
ISBN:

We report the first measurement of the top quark mass using the decay length technique in p{bar p} 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 695 pb−1 data sample recorded by the CDF II detector at Fermilab and extract a measurement of m{sub t} = 180.7{sub -13.4}{sup +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.

Measurement of the Top Quark Mass in P Anti-p Collisions at S**1/2

Measurement of the Top Quark Mass in P Anti-p Collisions at S**1/2
Author:
Publisher:
Total Pages: 23
Release: 2006
Genre:
ISBN:

We report the first measurement of the top quark mass using the decay length technique in p{bar p} 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 695 pb−1 data sample recorded by the CDF II detector at Fermilab and extract a measurement of m{sub t} = 180.7{sub -13.4}{sup +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.

Precision Measurement of the Mass of the Top Quark in P Anti-p Collisions

Precision Measurement of the Mass of the Top Quark in P Anti-p Collisions
Author:
Publisher:
Total Pages: 125
Release: 2007
Genre:
ISBN:

We report a measurement of the mass of the top quark (m{sub top}) in p{bar p} collisions at a center of mass energy of 1.96 TeV. The analysis is based on p{bar p}→t{bar t}→ lepton+jets data recorded with the D0 detector at the Fermilab Tevatron Collider. Events were preselected in the e+jets (913 events/pb of data) and in the [mu]+jets (871 events/pb of data) channels. These were analyzed through a comparison of the matrix element for the production and decay of the t{bar t} states with data, using a likelihood method and 'tagged' b quarks from the t → Wb decays.

Measurement of the Top Quark Mass Using Template Methods on Dilepton Events in P Anti-p Collisions at S**1/2

Measurement of the Top Quark Mass Using Template Methods on Dilepton Events in P Anti-p Collisions at S**1/2
Author:
Publisher:
Total Pages: 52
Release: 2006
Genre:
ISBN:

The authors describe a measurement of the top quark mass from events produced in p{bar p} collisions at a center-of-mass energy of 1.96 TeV, using the Collider Detector at Fermilab. They identify t{bar t} candidates where both W bosons from the top quarks decay into leptons (e[nu], [mu][nu], or [tau][nu]) from a data sample of 360 pb−1. The top quark mass is reconstructed in each event separately by three different methods, which draw upon simulated distributions of the neutrino pseudorapidity, t{bar t} longitudinal momentum, or neutrino azimuthal angle in order to extract probability distributions for the top quark mass. For each method, representative mass distributions, or templates, are constructed from simulated samples of signal and background events, and parameterized to form continuous probability density functions. A likelihood fit incorporating these parameterized templates is then performed on the data sample masses in order to derive a final top quark mass. Combining the three template methods, taking into account correlations in their statistical and systematic uncertainties, results in a top quark mass measurement of 170.1 ± 6.0(stat.) ± 4.1(syst.) GeV/c2.

Measurement of the Top Quark Pair Production Cross Section in P Anti-p Collisions at S**(1/2)

Measurement of the Top Quark Pair Production Cross Section in P Anti-p Collisions at S**(1/2)
Author: Gustavo J. Otero y Garzon
Publisher:
Total Pages: 378
Release: 2006
Genre:
ISBN:

The subject of this thesis is the measurement of the rate at which a top-antitop quark pair is produced in pp collisions at a center of mass energy of ps = 1:96 TeV. The data are collected with the D detector, a multi-purpose detector operating at the Fermilab Tevatron collider during Run II. A measurement of the top quark pair (t$\bar{t}$) production cross section ( [sigma]t$\bar{t}$) in p$\bar{p}$ collisions at a center of mass energy of 1.96 TeV is presented. The measurement is based on data recorded by the D0 Detector at the Fermilab Tevatron Collider, and preselected in the e+jets (366 pb-1) and [mu]+jets (363 pb-1) channels. The cross section is extracted by applying a lifetime-tagging technique to the data, and yields [sigma]t$\bar{t}$ = 6.96$+1.07\atop{-0.98}$(stat + syst) ± 0.45(lumi) pb; for a top quark mass mt =175 GeV, in good agreement with the Standard Model prediction.

Measurement of the Top Quark Mass Using Template Methods on Dilepton Events in P Anti-p Collisions at S**ư

Measurement of the Top Quark Mass Using Template Methods on Dilepton Events in P Anti-p Collisions at S**ư
Author:
Publisher:
Total Pages: 52
Release: 2006
Genre:
ISBN:

The authors describe a measurement of the top quark mass from events produced in p{bar p} collisions at a center-of-mass energy of 1.96 TeV, using the Collider Detector at Fermilab. They identify t{bar t} candidates where both W bosons from the top quarks decay into leptons (e?,??, or??) from a data sample of 360 pb−1. The top quark mass is reconstructed in each event separately by three different methods, which draw upon simulated distributions of the neutrino pseudorapidity, t{bar t} longitudinal momentum, or neutrino azimuthal angle in order to extract probability distributions for the top quark mass. For each method, representative mass distributions, or templates, are constructed from simulated samples of signal and background events, and parameterized to form continuous probability density functions. A likelihood fit incorporating these parameterized templates is then performed on the data sample masses in order to derive a final top quark mass. Combining the three template methods, taking into account correlations in their statistical and systematic uncertainties, results in a top quark mass measurement of 170.1 ± 6.0(stat.) ± 4.1(syst.) GeV/c2.

Measurement of the Top-quark Mass in All-hadronic Decays in P Anti-p Collisions at CDF II.

Measurement of the Top-quark Mass in All-hadronic Decays in P Anti-p Collisions at CDF II.
Author:
Publisher:
Total Pages: 7
Release: 2006
Genre:
ISBN:

We present a measurement of the top-quark mass, M{sub tpo}, in the all-hadronic decay channel t{bar t} --> WbW−{bar b} --> q1{bar q}2bq3{bar q}4{bar b}. The analysis is performed using 310 pb−1 of (square root)s = 1.96 TeV p{bar p} collisions collected with the CDF II detector using a multi-jet 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 M{sub top} = 177.1 ± 4.9(stat.) ± 4.7(syst.) GeV/c2.

Measurement of the Top Quark Mass in $p \bar{p}$ Collisions Using Events with Two Leptons

Measurement of the Top Quark Mass in $p \bar{p}$ Collisions Using Events with Two Leptons
Author:
Publisher:
Total Pages: 5
Release: 2012
Genre:
ISBN:

We present a measurement of the top quark mass (m{sub t}) in p{bar p} collisions at √s = 1.96 TeV using t{bar t} events with two leptons (ee, e? or??) in the final state in 4.3 fb−1 of data collected with the D0 detector at the Fermilab Tevatron collider. We analyze the kinematically underconstrained dilepton events by integrating over the neutrino rapidity distributions. We reduce the dominant systematic uncertainties from jet energy calibration using a correction obtained from t{bar t} → l + jets events. We also correct jets in simulated events to replicate the quark flavor dependence of the jet response in data. In combination with our previous analysis, we measure m{sub t} = 174.0 ± 2.4(stat) ± 1.4(syst) GeV.