Search for the Standard Model Higgs Boson in the WH2![tau] V B$\bar{b}$ Channel with the D0 Detector

Search for the Standard Model Higgs Boson in the WH2![tau] V B$\bar{b}$ Channel with the D0 Detector
Author:
Publisher:
Total Pages: 151
Release: 2009
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A search for the Standard Model Higgs boson is performed in 4.0 fb-1 of p$\bar{p}$ collisions at √s = 1.96 TeV, collected with the DØ detector at the Fermilab Tevatron. The final state considered is a pair of b-jets with large missing transverse energy and one hadronic tau decay as expected from the reaction p$\bar{p}$ → WH → [tau] v b$\bar{b}$. Boosted decision trees are used to discriminate the signal from the background. Good agreement is observed between data and expected backgrounds. For a Higgs boson mass of 115 GeV, a limit is set at 95% C.L. on the cross-section times branching fraction of (p$\bar{p}$→ (Z/W)H)×(H → b$\bar{b}$) which is 14 times larger than the Standard Model value.

Search for the Standard Model Higgs Boson in the WH{u2192} ? V B$\bar{b}$ Channel with the D0 Detector

Search for the Standard Model Higgs Boson in the WH{u2192} ? V B$\bar{b}$ Channel with the D0 Detector
Author:
Publisher:
Total Pages: 151
Release: 2009
Genre:
ISBN:

A search for the Standard Model Higgs boson is performed in 4.0 fb-1 of p$ar{p}$ collisions at √s = 1.96 TeV, collected with the DØ detector at the Fermilab Tevatron. The final state considered is a pair of b-jets with large missing transverse energy and one hadronic tau decay as expected from the reaction p$ar{p}$ → WH → ? v b$ar{b}$. Boosted decision trees are used to discriminate the signal from the background. Good agreement is observed between data and expected backgrounds. For a Higgs boson mass of 115 GeV, a limit is set at 95% C.L. on the cross-section times branching fraction of (p$ar{p}$→ (Z/W)H)×(H → b$ar{b}$) which is 14 times larger than the Standard Model value.

A Search for the Higgs Boson in the Zh Channel with the D0 Detector at the Fermilab Tevatron Collider

A Search for the Higgs Boson in the Zh Channel with the D0 Detector at the Fermilab Tevatron Collider
Author: James Matthew Heinmiller
Publisher:
Total Pages: 280
Release: 2006
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This analysis describes a search for a standard model Higgs boson produced in association with a Z boson through the decay mode ZH {yields} e{sup +}e{sup -}b{bar b} in p{bar p} collisions at {radical}s = 1.96 TeV at the Fermilab Tevatron Collider. The data sample used in this analysis corresponds to 452 pb{sup -1} of integrated luminosity accumulated with the D{null} detector. Agreement between data and standard model predictions is observed. A 95% confidence level upper exclusion limit for the {sigma}(p{bar p} {yields} ZH) x BR(H {yields} b{bar b}) channel is set between 3.2-8.2 pb for Higgs masses of 105 to 145 GeV.

Search for the Standard Model Higgs Boson in Z H ---] Nu Anti-nu B Anti-b Channel at

Search for the Standard Model Higgs Boson in Z H ---] Nu Anti-nu B Anti-b Channel at
Author:
Publisher:
Total Pages: 4
Release: 2009
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ISBN:

We present a search for a low mass Standard Model Higgs boson produced in association with a Z boson decaying invisibly into a pair of neutrinos at a center-of-mass energy of √s = 1.96 TeV with the D0 detector at the Fermilab Tevatron collider. The final state is characterized by the presence of two b-tagged jets from the Higgs boson decay and a large imbalance in the transverse energy of the event. This channel is very powerful because of the large Z → [nu]{anti {nu}} branching ratio, but also has many experimental challenges due to the large multijet background and the absence of visible carged leptons in the final state. We present the result with 5.2 fb−1 of data and discuss the recent improvements in the sensitivity.

Finding the Higgs Boson of the Standard Model in the Channel ZH {u2192} E+e-b$\bar{b}$ with the D0 Detector at the Tevatron; Recherche Du Boson de Higgs Du Nideke Standard Dans Le Canal ZH {u2192} E+e-b$\bar{b}$ Avec Le Detecteur DØ Aupres Du Tevatron

Finding the Higgs Boson of the Standard Model in the Channel ZH {u2192} E+e-b$\bar{b}$ with the D0 Detector at the Tevatron; Recherche Du Boson de Higgs Du Nideke Standard Dans Le Canal ZH {u2192} E+e-b$\bar{b}$ Avec Le Detecteur DØ Aupres Du Tevatron
Author:
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Total Pages: 162
Release: 2010
Genre:
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The organization of this thesis consists of three main ideas: the first presents the theoretical framework and experimental, as well as objects used in the analysis and the second relates to the various work tasks of service that I performed on the calorimeter, and the third is the search for the Higgs boson in the channel ZH → e+e-b$ar{b}$. Thus, this thesis has the following structure: Chapter 1 is an introduction to the standard model of particle physics and the Higgs mechanism; Chapter 2 is an overview of the complex and the acceleration of the Tevatron at Fermilab DØ detector; Chapter 3 is an introduction to physical objects used in this thesis; Chapter 4 presents the study made on correcting the energy measured in the calorimeter; Chapter 5 describes the study of certification of electrons in the calorimeter; Chapter 6 describes the study of certification of electrons in the intercryostat region of calorimeter; Chapter 7 Detailed analysis on the search for Higgs production in the channel ZH → e+e-b$ar{b}$; and Chapter 8 presents the final results of the calculations of upper limits to the production cross section of the Higgs boson on a range of low masses.

Search for the Standard Model Higgs Boson in the ZH-]vvbb Channel in 5.2 Fb-1 of P-pbar Collisions at Sqrt(s)

Search for the Standard Model Higgs Boson in the ZH-]vvbb Channel in 5.2 Fb-1 of P-pbar Collisions at Sqrt(s)
Author:
Publisher:
Total Pages:
Release: 2009
Genre:
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A search is performed for the standard model Higgs boson in 5.2 fb−1 of p{bar p} collisions at √s = 1.96 TeV, collected with the D0 detector at the Fermilab Tevatron Collider. The final state considered is a pair of b jets and large missing transverse energy, as expected from p{bar p} → ZH → [nu]{bar [nu]}b{bar b} production. The search is also sensitive to the WH → l{nu}b{bar b} channel when the charged lepton is not identified. For a Higgs boson mass of 115 GeV, a limit is set at the 95% C.L. on the cross section multiplied by branching fraction for (p{bar p} → (Z/W)H) x (H → b{bar b}) that is a factor of 3.7 larger than the standard model value, consistent with the factor of 4.6 expected.

Search for the Standard Model Higgs Boson in P$\bar{p}$ Interactions with the Decay Mode H {u2192} W+W- {u2192} ?+v?-v at the DØ Experiment

Search for the Standard Model Higgs Boson in P$\bar{p}$ Interactions with the Decay Mode H {u2192} W+W- {u2192} ?+v?-v at the DØ Experiment
Author:
Publisher:
Total Pages: 176
Release: 2010
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A search for the standard model Higgs boson in p$ar{p}$ collisions resulting in two muons and large missing transverse energy is presented. The analysis uses 4.2 fb-1 of integrated luminosity at a center-of-mass energy of √s = 1.96 TeV collected between April 2002 and December 2008 with the D0 detector at the Fermilab Tevatron collider. No significant excess above the background estimation is observed and limits are derived on Higgs boson production.

Search for the Standard Model Higgs Boson in the Missing Energy Topology with

Search for the Standard Model Higgs Boson in the Missing Energy Topology with
Author:
Publisher:
Total Pages: 139
Release: 2009
Genre:
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A search for the Standard Model Higgs boson in the missing energy and acoplanar b-jet topology is reported, using an integrated luminosity of 0.93 fb−1 recorded by the D0 detector at the Fermilab Tevatron p{bar p} Collider. The analysis includes signal contributions from p{bar p} → ZH → [nu]{bar {nu}}b{bar b}, as well as from WH production in which the charged lepton from the W boson decay is undetected. Neural networks are used to separate signal from background. In the absence of a signal, limits are set on [sigma](p{bar p} → VH) x B(H → b{bar b}) at the 95% C.L. of 2.6-2.3 pb, for Higgs boson masses in the range 105-135 GeV, where V = W, Z. The corresponding expected limits range from 2.8 to 2.0 pb. Potential improvements to the analysis with an extended dataset totalling 4 fb−1 are also discussed. Essential maintenance related to the increased luminosity and RunIIb upgrade was carried out on the impact parameter (IP) based b-tagging trigger tool and the effect of the changes on the b-tagger's performance was investigated.