Document Type

Thesis

Date of Degree

Summer 2013

Degree Name

MS (Master of Science)

Degree In

Physics

First Advisor

Jane Nachtman

Abstract

The main motivation of the Compact Muon Solenoid (CMS) experiment is to explore and to discover physics underlying electro-weak asymmetry breaking. Beside this, CMS detector provides an opportunity to do various experiments for detecting new physics signatures beyond the Standard Model (SM). Investigation of these signatures requires the identification and precise energy and moment measurement of electrons, muons, photons, and jets. The objective of this thesis is the calculation of the efficiencies for the measurement of W charge asymmetry in inclusive pp→W (μυ) production. The charge asymmetry is defined to be the difference between W^+ and W^- bosons, normalized to the sum. This asymmetry is sensitive to the u-quark and d-quark ratios in the proton and precise measurement of the W charge asymmetry can provides new insights to the proton structure functions. Therefore, to improve understanding of SM backgrounds in search for new physics, the moun trigger, isolation, reconstruction, identification efficiencies has been studied using partial data collected by the CMS detector during pp collisions at the LHC in 2011. The dataset corresponds to an integrated luminosity of 2.31 fb-1. The efficiencies are measured as functions of the decay muon pseudo rapidity and transverse momentum based on "tag and probe" method. The efficiency measurements are compared to their estimated value from the Monte Carlo simulations so as to provide scaling factors to correct to the residual mis-modeling of the CMS muon performance. The comparison with simulations based on MC simulations opens a gate for validation of the detector simulation and optimization of selection strategies.

Keywords

charge asymmetry, CMS, experimental high energy, hasan ogul iowa, muon efficiency

Pages

viii, 49 pages

Bibliography

Includes bibliographical references (pages 48-49).

Comments

This thesis has been optimized for improved web viewing. If you require the original version, contact the University Archives at the University of Iowa: http://www.lib.uiowa.edu/sc/contact/.

Copyright

Copyright 2013 Hasan Ogul

Included in

Physics Commons

Share

COinS