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Title: Measurement of the top quark mass in pp collisions at {radical}(s)=1.96 TeV using the decay length technique

Abstract

We report the first measurement of the top quark mass using the decay length technique in pp 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{sup -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/c{sup 2}. 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.

Authors:
; ; ; ; ; ; ; ; ; ; ; ; ; ;  [1]; ; ; ; ;  [2]
  1. University of Illinois, Urbana, Illinois 61801 (United States)
  2. Enrico Fermi Institute, University of Chicago, Chicago, Illinois 60637 (United States) (and others)
Publication Date:
OSTI Identifier:
21020232
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 7; Other Information: DOI: 10.1103/PhysRevD.75.071102; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; BEAUTY PARTICLES; FERMILAB COLLIDER DETECTOR; GEV RANGE; JET MODEL; LEPTONS; PROTON-PROTON INTERACTIONS; REST MASS; T QUARKS; TEV RANGE; TRANSVERSE ENERGY

Citation Formats

Abulencia, A., Budd, S., Ciobanu, C. I., Errede, D., Errede, S., Gerberich, H., Grundler, U., Junk, T. R., Kraus, J., Marino, C. P., Pitts, K., Rogers, E., Taffard, A., Veramendi, G., Zhang, X., Adelman, J., Brubaker, E., Fedorko, W. T., Furic, I., and Grosso-Pilcher, C. Measurement of the top quark mass in pp collisions at {radical}(s)=1.96 TeV using the decay length technique. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.071102.
Abulencia, A., Budd, S., Ciobanu, C. I., Errede, D., Errede, S., Gerberich, H., Grundler, U., Junk, T. R., Kraus, J., Marino, C. P., Pitts, K., Rogers, E., Taffard, A., Veramendi, G., Zhang, X., Adelman, J., Brubaker, E., Fedorko, W. T., Furic, I., & Grosso-Pilcher, C. Measurement of the top quark mass in pp collisions at {radical}(s)=1.96 TeV using the decay length technique. United States. doi:10.1103/PHYSREVD.75.071102.
Abulencia, A., Budd, S., Ciobanu, C. I., Errede, D., Errede, S., Gerberich, H., Grundler, U., Junk, T. R., Kraus, J., Marino, C. P., Pitts, K., Rogers, E., Taffard, A., Veramendi, G., Zhang, X., Adelman, J., Brubaker, E., Fedorko, W. T., Furic, I., and Grosso-Pilcher, C. Sun . "Measurement of the top quark mass in pp collisions at {radical}(s)=1.96 TeV using the decay length technique". United States. doi:10.1103/PHYSREVD.75.071102.
@article{osti_21020232,
title = {Measurement of the top quark mass in pp collisions at {radical}(s)=1.96 TeV using the decay length technique},
author = {Abulencia, A. and Budd, S. and Ciobanu, C. I. and Errede, D. and Errede, S. and Gerberich, H. and Grundler, U. and Junk, T. R. and Kraus, J. and Marino, C. P. and Pitts, K. and Rogers, E. and Taffard, A. and Veramendi, G. and Zhang, X. and Adelman, J. and Brubaker, E. and Fedorko, W. T. and Furic, I. and Grosso-Pilcher, C.},
abstractNote = {We report the first measurement of the top quark mass using the decay length technique in pp 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{sup -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/c{sup 2}. 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.},
doi = {10.1103/PHYSREVD.75.071102},
journal = {Physical Review. D, Particles Fields},
number = 7,
volume = 75,
place = {United States},
year = {Sun Apr 01 00:00:00 EDT 2007},
month = {Sun Apr 01 00:00:00 EDT 2007}
}
  • We present a measurement of the top quark mass in the all hadronic channel (tt{yields}bbq{sub 1}q{sub 2}q{sub 3}q{sub 4}) using 943 pb{sup -1} of pp collisions at {radical}(s)=1.96 TeV collected at the CDF II detector at Fermilab (CDF). We apply the standard model production and decay matrix element (ME) to tt candidate events. We calculate per-event probability densities according to the ME calculation and construct template models of signal and background. The scale of the jet energy is calibrated using additional templates formed with the invariant mass of pairs of jets. These templates form an overall likelihood function that dependsmore » on the top quark mass and on the jet energy scale (JES). We estimate both by maximizing this function. Given 72 observed events, we measure a top quark mass of 171.1{+-}3.7(stat+JES){+-}2.1(syst) GeV/c{sup 2}. The combined uncertainty on the top quark mass is 4.3 GeV/c{sup 2}.« less
  • 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{sup -1} data sample recorded by the CDF II detector at Fermilab and extract a measurementmore » of m{sub t} = 180.7{sub -13.4}{sup +15.5}(stat.) {+-} 8.6 (syst.) GeV/c{sup 2}. 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.« less
  • We describe a measurement of the top quark mass from events produced in pp collisions at a center-of-mass energy of 1.96 TeV, using the Collider Detector at Fermilab. We identify tt 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{sup -1}. The top quark mass is reconstructed in each event separately by three different methods, which draw upon simulated distributions of the neutrino pseudorapidity, tt longitudinal momentum, or neutrino azimuthal angle in order to extract probability distributions for the top quark mass. For each method, representativemore » mass distributions, or templates, are constructed from simulated samples of signal and background events, and parametrized to form continuous probability density functions. A likelihood fit incorporating these parametrized 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/c{sup 2}.« less
  • This paper describes a measurement of the top quark mass, M{sub top}, with the dynamical likelihood method (DLM) using the CDF II detector at the Fermilab Tevatron. The Tevatron produces top/antitop (tt) pairs in pp collisions at a center-of-mass energy of 1.96 TeV. The data sample used in this analysis was accumulated from March 2002 through August 2004, which corresponds to an integrated luminosity of 318 pb{sup -1}. We use the tt candidates in the 'lepton+jets' decay channel, requiring at least one jet identified as a b quark by finding a displaced secondary vertex. The DLM defines a likelihood formore » each event based on the differential cross section as a function of M{sub top} per unit phase space volume of the final partons, multiplied by the transfer functions from jet to parton energies. The method takes into account all possible jet combinations in an event, and the likelihood is multiplied event by event to derive the top quark mass by the maximum likelihood method. Using 63 tt candidates observed in the data, with 9.2 events expected from background, we measure the top quark mass to be 173.2(+2.6/-2.4)(stat.){+-}3.2(syst.) GeV/c{sup 2}, or 173.2(+4.1/-4.0) GeV/c{sup 2}.« less
  • We report measurements of the polarization of W bosons from top-quark decays using 2.7 fb{sup -1} of pp collisions collected by the CDF II detector. Assuming a top-quark mass of 175 GeV/c{sup 2}, three measurements are performed. A simultaneous measurement of the fraction of longitudinal (f{sub 0}) and right-handed (f{sub +}) W bosons yields the model-independent results f{sub 0}=0.88{+-}0.11(stat){+-}0.06(syst) and f{sub +}=-0.15{+-}0.07(stat){+-}0.06(syst) with a correlation coefficient of -0.59. A measurement of f{sub 0}[f{sub +}] constraining f{sub +}[f{sub 0}] to its standard model value of 0.0 [0.7] yields f{sub 0}=0.70{+-}0.07(stat){+-}0.04(syst)[f{sub +}=-0.01{+-}0.02(stat){+-}0.05(syst)]. All these results are consistent with standard model expectations. Wemore » achieve the single most precise measurements of f{sub 0} for both the model-independent and model-dependent determinations.« less