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Title: A Measurement of the t anti-t Cross Section in p anti-p Collisions at s**(1/2) = 1.96-TeV using Dilepton Events with a Lepton plus Track Selection

Abstract

This paper reports a measurement of the cross section for the pair production of top quarks in p{bar p} collisions at {radical}s = 1.96 TeV at the Fermilab Tevatron. The data was collected from the CDF II detector in a set of runs with a total integrated luminosity of 1.1 fb{sup -1}. The cross section is measured in the dilepton channel, the subset of t{bar t} events in which both top quarks decay through t {yields} Wb {yields} {ell}{nu}b, where {ell} = e, {mu}, or {tau}. The lepton pair is reconstructed as one identified electron or muon and one isolated track. The use of an isolated track to identify the second lepton increases the t{bar t} acceptance, particularly for the case in which one W decays as W {yields} {tau}{nu}. The purity of the sample may be further improved at the cost of a reduction in the number of signal events, by requiring an identified b-jet. They present the results of measurements performed with and without the request of an identified b-jet. the former is the first published CDF result for which a b-jet requirement is added to the dilepton selection. In the CDF data there are 129 pretag leptonmore » + track candidate events, of which 69 are tagged. With the tagging information, the sample is divided into tagged and untagged sub-samples, and a combined cross section is calculated by maximizing a likelihood. The result is {sigma}{sub t{bar t}} = 9.6 {+-} 1.2(stat.){sub -0.5}{sup +0.6}(sys.) {+-} 0.6(lum.) pb, assuming a branching ratio of BR(W {yields} {ell}{nu}) = 10.8% and a top mass of m{sub t} = 175 GeV/c{sup 2}.« less

Authors:
; ; ; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
951343
Report Number(s):
FERMILAB-PUB-09-091-E
arXiv eprint number arXiv:0903.5263; TRN: US0902199
DOE Contract Number:  
AC02-07CH11359
Resource Type:
Journal Article
Journal Name:
Submitted to Phys.Rev.D
Additional Journal Information:
Journal Name: Submitted to Phys.Rev.D
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; BRANCHING RATIO; CROSS SECTIONS; DECAY; ELECTRONS; FERMILAB COLLIDER DETECTOR; FERMILAB TEVATRON; LEPTONS; LUMINOSITY; MUONS; PAIR PRODUCTION; T QUARKS; Experiment-HEP

Citation Formats

Aaltonen, T, /Helsinki Inst. of Phys., Adelman, Jahred A, /Chicago U., EFI, Akimoto, T, /Tsukuba U., Alvarez Gonzalez, B, /Cantabria Inst. of Phys., Amerio, S, /INFN, Padua, Amidei, Dante E, /Michigan U., Anastassov, A, /Northwestern U., Annovi, Alberto, /Frascati, Antos, Jaroslav, /Comenius U., Apollinari, G, /Fermilab, Apresyan, A, and /Purdue U. /Waseda U. A Measurement of the t anti-t Cross Section in p anti-p Collisions at s**(1/2) = 1.96-TeV using Dilepton Events with a Lepton plus Track Selection. United States: N. p., 2009. Web. doi:10.1103/PhysRevD.79.112007.
Aaltonen, T, /Helsinki Inst. of Phys., Adelman, Jahred A, /Chicago U., EFI, Akimoto, T, /Tsukuba U., Alvarez Gonzalez, B, /Cantabria Inst. of Phys., Amerio, S, /INFN, Padua, Amidei, Dante E, /Michigan U., Anastassov, A, /Northwestern U., Annovi, Alberto, /Frascati, Antos, Jaroslav, /Comenius U., Apollinari, G, /Fermilab, Apresyan, A, & /Purdue U. /Waseda U. A Measurement of the t anti-t Cross Section in p anti-p Collisions at s**(1/2) = 1.96-TeV using Dilepton Events with a Lepton plus Track Selection. United States. doi:10.1103/PhysRevD.79.112007.
Aaltonen, T, /Helsinki Inst. of Phys., Adelman, Jahred A, /Chicago U., EFI, Akimoto, T, /Tsukuba U., Alvarez Gonzalez, B, /Cantabria Inst. of Phys., Amerio, S, /INFN, Padua, Amidei, Dante E, /Michigan U., Anastassov, A, /Northwestern U., Annovi, Alberto, /Frascati, Antos, Jaroslav, /Comenius U., Apollinari, G, /Fermilab, Apresyan, A, and /Purdue U. /Waseda U. Sun . "A Measurement of the t anti-t Cross Section in p anti-p Collisions at s**(1/2) = 1.96-TeV using Dilepton Events with a Lepton plus Track Selection". United States. doi:10.1103/PhysRevD.79.112007. https://www.osti.gov/servlets/purl/951343.
@article{osti_951343,
title = {A Measurement of the t anti-t Cross Section in p anti-p Collisions at s**(1/2) = 1.96-TeV using Dilepton Events with a Lepton plus Track Selection},
author = {Aaltonen, T and /Helsinki Inst. of Phys. and Adelman, Jahred A and /Chicago U., EFI and Akimoto, T and /Tsukuba U. and Alvarez Gonzalez, B and /Cantabria Inst. of Phys. and Amerio, S and /INFN, Padua and Amidei, Dante E and /Michigan U. and Anastassov, A and /Northwestern U. and Annovi, Alberto and /Frascati and Antos, Jaroslav and /Comenius U. and Apollinari, G and /Fermilab and Apresyan, A and /Purdue U. /Waseda U.},
abstractNote = {This paper reports a measurement of the cross section for the pair production of top quarks in p{bar p} collisions at {radical}s = 1.96 TeV at the Fermilab Tevatron. The data was collected from the CDF II detector in a set of runs with a total integrated luminosity of 1.1 fb{sup -1}. The cross section is measured in the dilepton channel, the subset of t{bar t} events in which both top quarks decay through t {yields} Wb {yields} {ell}{nu}b, where {ell} = e, {mu}, or {tau}. The lepton pair is reconstructed as one identified electron or muon and one isolated track. The use of an isolated track to identify the second lepton increases the t{bar t} acceptance, particularly for the case in which one W decays as W {yields} {tau}{nu}. The purity of the sample may be further improved at the cost of a reduction in the number of signal events, by requiring an identified b-jet. They present the results of measurements performed with and without the request of an identified b-jet. the former is the first published CDF result for which a b-jet requirement is added to the dilepton selection. In the CDF data there are 129 pretag lepton + track candidate events, of which 69 are tagged. With the tagging information, the sample is divided into tagged and untagged sub-samples, and a combined cross section is calculated by maximizing a likelihood. The result is {sigma}{sub t{bar t}} = 9.6 {+-} 1.2(stat.){sub -0.5}{sup +0.6}(sys.) {+-} 0.6(lum.) pb, assuming a branching ratio of BR(W {yields} {ell}{nu}) = 10.8% and a top mass of m{sub t} = 175 GeV/c{sup 2}.},
doi = {10.1103/PhysRevD.79.112007},
journal = {Submitted to Phys.Rev.D},
number = ,
volume = ,
place = {United States},
year = {2009},
month = {3}
}