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Title: A search for z boson pair production at the Fermilab Tevatron Collider

Abstract

This dissertation describes a search for Z/γ* boson pair production decaying into μμμμ, μμee, and eeee final states with approximately 1 fb -1 of data at the Fermilab Tevatron Collider at √s = 1.96 TeV. The small cross section times branching ratio for each channel mandated a thorough study of the acceptance and efficiencies. After optimization, 1.7 ± 0.1 events are expected for Standard Model production with a background of 0.13 ± 0.03 events. One event was found in the μμee channel. A cross section limit of 4.4 pb is determined at a 95% confidence level for Standard Model production. Additionally, one parameter and two parameter 95% C.L. limits are found for the anomalous neutral trilinear gauge couplings ZZZ* and ZZγ*. The one parameter 95% C.L. coupling limits with a form factor scale of 1.2 TeV are: -0.28 < f$$Z\atop{40}$$ < 0.28, -0.31 < f$$Z\atop{50}$$ < 0.29, -0.26 < f$$γ\atop{40}$$ < 0.26, and -0.30 < f$$γ\atop{50}$$ < 0.28.

Authors:
 [1]
  1. Univ. of Maryland, College Park, MD (United States)
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
924530
Report Number(s):
FERMILAB-THESIS-2007-54
TRN: US0802911
DOE Contract Number:
AC02-07CH11359
Resource Type:
Thesis/Dissertation
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; BOSONS; BRANCHING RATIO; CROSS SECTIONS; FERMILAB TEVATRON; FORM FACTORS; OPTIMIZATION; PAIR PRODUCTION; PRODUCTION; STANDARD MODEL; Experiment-HEP

Citation Formats

Jarvis, Chad Ryan. A search for z boson pair production at the Fermilab Tevatron Collider. United States: N. p., 2007. Web. doi:10.2172/924530.
Jarvis, Chad Ryan. A search for z boson pair production at the Fermilab Tevatron Collider. United States. doi:10.2172/924530.
Jarvis, Chad Ryan. Mon . "A search for z boson pair production at the Fermilab Tevatron Collider". United States. doi:10.2172/924530. https://www.osti.gov/servlets/purl/924530.
@article{osti_924530,
title = {A search for z boson pair production at the Fermilab Tevatron Collider},
author = {Jarvis, Chad Ryan},
abstractNote = {This dissertation describes a search for Z/γ* boson pair production decaying into μμμμ, μμee, and eeee final states with approximately 1 fb-1 of data at the Fermilab Tevatron Collider at √s = 1.96 TeV. The small cross section times branching ratio for each channel mandated a thorough study of the acceptance and efficiencies. After optimization, 1.7 ± 0.1 events are expected for Standard Model production with a background of 0.13 ± 0.03 events. One event was found in the μμee channel. A cross section limit of 4.4 pb is determined at a 95% confidence level for Standard Model production. Additionally, one parameter and two parameter 95% C.L. limits are found for the anomalous neutral trilinear gauge couplings ZZZ* and ZZγ*. The one parameter 95% C.L. coupling limits with a form factor scale of 1.2 TeV are: -0.28 < f$Z\atop{40}$ < 0.28, -0.31 < f$Z\atop{50}$ < 0.29, -0.26 < f$γ\atop{40}$ < 0.26, and -0.30 < f$γ\atop{50}$ < 0.28.},
doi = {10.2172/924530},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}

Thesis/Dissertation:
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  • Two high energy particle physics analyses are presented in this PhD report using events with two leptons oppositely charged and with missing transverse energy. These events are selected using 9.7 fb-1 of total pp collisions data collected with the DØ detector at the TeVatron at √s=1.96 TeV.The first analysis is the research of the Higgs boson decaying in the H→WW→μνμν channel. No significant excess above the background prediction is observed.Upper limits on Higgs boson production cross-section are computed in the standard model framework but also in the 4th generation of fermions and in the fermiophobic coupling to Higgs boson hypotheses.more » In order to validate the research methodology, the W boson pair production cross-section is measured.The second analysis is the measurement of the forward-backward asymmetry of the tt pair production. This is the first measurement in the dileptonic channel at DØ experiment. In this context, a new tt pair kinematic reconstruction is used (matrix element method) to give a raw measurement of the forward-backward asymmetry. Thanks to a dedicated calibration method, we give a final measurement of AFB=18.0 ± 6.0 (stat) ± 3.3 (syst).« less
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