Measurement of cross section times branching ratio for W boson + photon and Z boson + photon and search for anomalous W boson-photon and Z boson-photon couplings at 1.8 TeV

Measurements of the production cross section times branching ratio for W + γ and Z + γ processes, where the W decays into a muon and neutrino and the Z decays into a muon pair, have been made from the analysis of 18.6 $\pm$ 0.7 $pb\sp{-1}$ of high-$P\sb{T}$ muon data from proton-antiproton (pp) collisions. The data were collected with the Collider Detector at Fermilab (CDF) during the 1992-93 run. In a search for central photons (\vert\eta\vert < 1.1) with transverse energy above 7 GeV and angular separation from the muon by at least $\Delta R$ = 0.7 we find 7 Wγ and 4 Zγ candidates. This translates into cross section times branching ratios of 9.0 $\pm$ 6.4 pb for the Wγ process and 6.6 $\pm$ 3.4 pb for the Zγ process. Separate measurements were made for photon $E\sb{T}$ values above 11 GeV and 15 GeV. The cross section times branching ratio results were used to calculate a series of cross section ratios. An analysis designed to search for anomalous couplings between the gauge bosons was also carried out using these results. Assuming only one anomalous coupling to be non-zero at a time, the 95% CL limits on Wγ anomalous couplings are, -3.7 < \Delta\kappa < 3.7, -1.2 < \lambda < 1.2, -3.8 < \tilde\kappa < 3.8 and $-1.2 < \tilde\lambda <$ 1.2. For ZZγ anomalous couplings the experimental limits are measured to be, at the 95% CL, $-4.6 < h\sbsp{30}{Z}(h\sbsp{10}{Z}) <$ 4.6 and $-1.1 < h\sbsp{40}{Z}(h\sbsp{20}{Z}) <$ 1.1. For Zγγ anomalous couplings the experimental limits are measured to be, at, the 95% CL, -4.9 < h\sbsp{30}{γ}(h\sbsp{10}{γ}) < 4.9 and -1.2 < h\sbsp{40}{γ}(h\sbsp{20}{γ}) < 1.2. Limits are placed on electromagnetic multipole moments for both the W and Z bosons using the measured limits of the anomalous couplings, and are presented in this thesis. All of the measurements presented in this thesis are consistent with Standard Model expectations.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Physics

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2011

Author dc:creator

• Vondracek, Mark Frank

Contributors dc:contributor

• Liss, Tony M.

• Physics, Elementary Particles and High Energy

Statement dc:rights

• Copyright 1994 Vondracek, Mark Frank

Language dc:language

eng

Identifier

AAI9522185
(UMI)AAI9522185

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/20424