Measurement of the top quark mass in the all hadronic final state at the Dø experiment

The top quark is the heaviest fermion observed to date. A precise measurement of its mass and W boson mass is important to indirect measurements of Higgs boson mass. Furthermore, the top quark mass, W boson mass and Higgs boson mass may test the Standard Model using the correlations between them. He...

Full description

Saved in:
Bibliographic Details
Main Author: Jayasinghe, Ayesh
Format: Dissertation
Language:English
Published: ProQuest Dissertations & Theses 01-01-2013
Subjects:
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The top quark is the heaviest fermion observed to date. A precise measurement of its mass and W boson mass is important to indirect measurements of Higgs boson mass. Furthermore, the top quark mass, W boson mass and Higgs boson mass may test the Standard Model using the correlations between them. Here in this thesis, we present a measurement of the top quark mass in the all hadronic final state using the template method. This final state has the advantage of being fully reconstructed in the detector and having the largest branching fraction. The measurement is performed on 4033 candidate events collected using the DØ detector. The data is collected from pp collisions generated at √s =1.96 GeV by the TEVATRON accelerator, Fermi National Accelerator Laboratory, Batavia IL. This is a two dimensional measurement formulated to extract the top quark mass as well as lower the systematic uncertainty due to the jet energy scale calibration. A kinematic fitter is employed to build the templates of signal and background for various input top quark mass points and jet energy scale variations. These templates are compared to data to obtain the fitted top quark mass, jet energy scale shift and their uncertainties. The obtained top quark mass is mt = 170.4 ± 1.7 (stat) ± 2.9 (sys) GeV.
ISBN:1303182602
9781303182600