Single Top Quark Production and Vtb at the Tevatron

Single Top Quark Production and Vtb at the Tevatron PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 5

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Book Description
Single top quark production via the electroweak interaction was observed by the D0 and CDF collaborations at the Tevatron proton-antiproton collider at Fermilab. Multivariate analysis techniques are employed to extract the small single top quark signal. The combined Tevatron cross section is 2.76{sub -0.47}{sup +0.58} pb. This corresponds to a lower limit on the CKM matrix element.

Single Top Quark Production and Vtb at the Tevatron

Single Top Quark Production and Vtb at the Tevatron PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 5

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Book Description
Single top quark production via the electroweak interaction was observed by the D0 and CDF collaborations at the Tevatron proton-antiproton collider at Fermilab. Multivariate analysis techniques are employed to extract the small single top quark signal. The combined Tevatron cross section is 2.76{sub -0.47}{sup +0.58} pb. This corresponds to a lower limit on the CKM matrix element.

Tevatron Combination of Single Top Quark Production and Vtb Measurement

Tevatron Combination of Single Top Quark Production and Vtb Measurement PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 3

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Book Description
After the first observation of the inclusive single top-quark production in the s- and t-channels by CDF and D0, both Tevatron collaborations combined their measurements using the distributions of their multivariate discriminants. A Bayesian analysis is used to extract the cross section at a center of mass energy of 1.96 TeV from 3.2 fb−1 (CDF) and 2.3 fb−1 (D0) of data, respectively. For a top quark mass of 170 GeV/c2, a cross section of 2.76 + 0.58 - 0.47 pb is extracted while the CKM matrix element.

Top Quark Physics at Hadron Colliders

Top Quark Physics at Hadron Colliders PDF Author: Arnulf Quadt
Publisher: Springer Science & Business Media
ISBN: 3540710604
Category : Science
Languages : en
Pages : 166

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Book Description
This will be a required acquisition text for academic libraries. More than ten years after its discovery, still relatively little is known about the top quark, the heaviest known elementary particle. This extensive survey summarizes and reviews top-quark physics based on the precision measurements at the Fermilab Tevatron Collider, as well as examining in detail the sensitivity of these experiments to new physics. Finally, the author provides an overview of top quark physics at the Large Hadron Collider.

Discovery of Single Top Quark Production

Discovery of Single Top Quark Production PDF Author: Dag Gillberg
Publisher: Springer Science & Business Media
ISBN: 1441977996
Category : Science
Languages : en
Pages : 149

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Book Description
The top quark is by far the heaviest known fundamental particle with a mass nearing that of a gold atom. Because of this strikingly high mass, the top quark has several unique properties and might play an important role in electroweak symmetry breaking—the mechanism that gives all elementary particles mass. Creating top quarks requires access to very high energy collisions, and at present only the Tevatron collider at Fermilab is capable of reaching these energies. Until now, top quarks have only been observed produced in pairs via the strong interaction. At hadron colliders, it should also be possible to produce single top quarks via the electroweak interaction. Studies of single top quark production provide opportunities to measure the top quark spin, how top quarks mix with other quarks, and to look for new physics beyond the standard model. Because of these interesting properties, scientists have been looking for single top quarks for more than 15 years. This thesis presents the first discovery of single top quark production. It documents one of the flagship measurements of the D0 experiment, a collaboration of more than 600 physicists from around the world. It describes first observation of a physical process known as “single top quark production”, which had been sought for more than 10 years before its eventual discovery in 2009. Further, his thesis describes, in detail, the innovative approach Dr. Gillberg took to this analysis. Through the use of Boosted Decision Trees, a machine-learning technique, he observed the tiny single top signal within an otherwise overwhelming background. This Doctoral Thesis has been accepted by Simon Fraser University, Burnaby, BC, Canada.

Measurement of the Electroweak Top Quark Production Cross Section and the CKM Matrix Element Vtb with the D0 Experiment

Measurement of the Electroweak Top Quark Production Cross Section and the CKM Matrix Element Vtb with the D0 Experiment PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 466

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Book Description
At particle accelerators the Standard Model has been tested and will be tested further to a great precision. The data analyzed in this thesis have been collected at the world's highest energetic-collider, the Tevatron, located at the Fermi National Accelerator Laboratory (FNAL) in the vicinity of Chicago, IL, USA. There, protons and antiprotons are collided at a center-of-mass energy of √s = 1.96 TeV. The discovery of the top quark was one of the remarkable results not only for the CDF and D0 experiments at the Tevatron collider, but also for the Standard Model, which had predicted the existence of the top quark because of symmetry arguments long before already. Still, the Tevatron is the only facility able to produce top quarks. The predominant production mechanism of top quarks is the production of a top-antitop quark pair via the strong force. However, the Standard Model also allows the production of single top quarks via the electroweak interaction. This process features the unique opportunity to measure the.

Summary of Single Top Quark Production at the Tevatron

Summary of Single Top Quark Production at the Tevatron PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
The production of single-top quarks occurs via the weak interaction at the Fermilab Tevatron proton-antiproton collider. Single top quark events are selected in the lepton+jets final state by CDF and D0 and in the missing transverse energy plus jets final state by CDF. Multivariate classifiers separate the s-channel and t-channel single-top signals from the large backgrounds. The combination of CDF and D0 results leads to the first observation of the s-channel mode of single top quark production. The t-channel and single top combined cross sections have also been measured.

Studies of Single Top Quark Production at the Tevatron

Studies of Single Top Quark Production at the Tevatron PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 5

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Book Description
In this paper we present several measurements of single top quark production from the CDF and D0 experiments at the Tevatron. The various analyses utilize integrated luminosity ranging from 2.1 to 4.8 fb−1. The results include the observation of single top production with a combined cross section of 2.76{sub -0.47}{sup +0.58} pb for a top quark mass of 170 GeV/c2, as well as measurements of top quark polarization and first evidence for t-channel production.

Observation of Single Top Quark Production at the Tevatron Collider

Observation of Single Top Quark Production at the Tevatron Collider PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 30

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Observation of S-channel Single Top Quark Production at the Tevatron

Observation of S-channel Single Top Quark Production at the Tevatron PDF Author: Matteo Cremonesi
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Observation of Single Top Quark Production at the Tevatron

Observation of Single Top Quark Production at the Tevatron PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 4

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Book Description
This paper reports on the first observation of electroweak production of single top quarks by the D0 and CDF collaborations. At Fermilab's 1.96 TeV proton-antiproton collider, a few thousand events are selected from several inverse femtobarns of data that contain an isolated electron or muon and/or missing transverse energy, together with jets that originate from the decays of b quarks. Using sophisticated multivariate analyses to separate signal from background, the D0 collaboration measures a cross section [sigma] (p{bar p} → tb + X, tqb + X) = 3.94 ± 0.88 pb (for a top quark mass of 170 GeV) and the CDF collaboration measures a value of 2.3{sub -0.5}{sup +0.6} pb (for a top quark mass of 175 GeV). These values are consistent with theoretical predictions at next-to-leading order precision. Both measurements have a significance of 5.0 standard deviations, meeting the benchmark to be considered unambiguous observation.