Persistent Link:
http://hdl.handle.net/10150/195885
Title:
Measurement of the W Boson Helicity in Top Quark Decays
Author:
Gmyrek, Bryan David
Issue Date:
2007
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
A measurement of the fraction, f⁺, of right-handed W bosons produced in top quark decays is presented. This analysis is based on a sample corresponding to an integrated luminosity of 370 pb⁻¹, collected by the D⊘ detector at the Fermilab Tevatron pp Collider at √s = 1.96 TeV. The helicity angle, θ*, is reconstructed for each lepton. f⁺ is determined by comparing the cos θ* distribution from the data with that for the expected background and signal for various values of f⁺. The fraction of longitudinal W bosons, f⁰, is assumed to be 0.7 as predicted by the standard model. This yields f⁺ = 0.109 ± 0.094 (stat) ± 0.063 (syst), consistent with the standard model prediction of f⁺ = 3.6× 10⁻⁴. The possibility that both f⁺ and f⁰ stray from standard model values is also investigated. In this case cos θ* distributions for each possible W helicity state, along with the backgrounds, are fit to the cos θ* distribution for the data. The best fit values are f⁺ = 0.82 ± 0.30(stat) and f⁰ = −0.58 ± 0.50(stat).
Type:
text; Electronic Dissertation
Keywords:
top quark right handed polarization
Degree Name:
PhD
Degree Level:
doctoral
Degree Program:
Physics; Graduate College
Degree Grantor:
University of Arizona
Advisor:
Johns, Kenneth A.; Varnes, Erich W.
Committee Chair:
Johns, Kenneth A.; Varnes, Erich W.

Full metadata record

DC FieldValue Language
dc.language.isoENen_US
dc.titleMeasurement of the W Boson Helicity in Top Quark Decaysen_US
dc.creatorGmyrek, Bryan Daviden_US
dc.contributor.authorGmyrek, Bryan Daviden_US
dc.date.issued2007en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractA measurement of the fraction, f⁺, of right-handed W bosons produced in top quark decays is presented. This analysis is based on a sample corresponding to an integrated luminosity of 370 pb⁻¹, collected by the D⊘ detector at the Fermilab Tevatron pp Collider at √s = 1.96 TeV. The helicity angle, θ*, is reconstructed for each lepton. f⁺ is determined by comparing the cos θ* distribution from the data with that for the expected background and signal for various values of f⁺. The fraction of longitudinal W bosons, f⁰, is assumed to be 0.7 as predicted by the standard model. This yields f⁺ = 0.109 ± 0.094 (stat) ± 0.063 (syst), consistent with the standard model prediction of f⁺ = 3.6× 10⁻⁴. The possibility that both f⁺ and f⁰ stray from standard model values is also investigated. In this case cos θ* distributions for each possible W helicity state, along with the backgrounds, are fit to the cos θ* distribution for the data. The best fit values are f⁺ = 0.82 ± 0.30(stat) and f⁰ = −0.58 ± 0.50(stat).en_US
dc.typetexten_US
dc.typeElectronic Dissertationen_US
dc.subjecttop quark right handed polarizationen_US
thesis.degree.namePhDen_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplinePhysicsen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorJohns, Kenneth A.en_US
dc.contributor.advisorVarnes, Erich W.en_US
dc.contributor.chairJohns, Kenneth A.en_US
dc.contributor.chairVarnes, Erich W.en_US
dc.contributor.committeememberFang, Li-Zhien_US
dc.contributor.committeememberGarcia, J.D.en_US
dc.contributor.committeememberMilsom, Drewen_US
dc.identifier.proquest2318en_US
dc.identifier.oclc659748179en_US
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