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Title: Measurement of the Forward-Backward Asymmetry in $$\gamma/Z$$ boson to Dilepton Events in Compact Muon Solenoid at a Center-of-mass Energy of 7 TeV

Thesis/Dissertation ·
DOI:https://doi.org/10.2172/1156433· OSTI ID:1156433
 [1]
  1. Texas Tech Univ., Lubbock, TX (United States)

The forward-backward asymmetry parameter (AFB) as a function of dilepton invariant mass in Z/γ* →l+l- (l=e or μ) at √s=7 TeV is measured using 2.2 fb-1 of pp collision data in 2011. The forward-backward asymmetry measurement is performed using muons within |η| < 2.1 and electrons within |η| < 2.4 in a wide mass range between 40 GeV/c2 to 1000 GeV/c2. The forward-backward asymmetry is also measured for the first time in a large rapidity range of |η| < 5 with electrons using the CMS forward calorimeters and results in a less diluted AFB measurement, as expected. The forward-backward asymmetry parameters are unfolded in three stages, limited pre-FSR, full pre-FSR, and non-diluted stage in order to obtain parton level AFB. The muon and electron results are combined, and the individual and combined results are found to be consistent with the Standard Model prediction within statistical and systematic uncertainties.

Research Organization:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Organization:
USDOE Office of Science (SC), High Energy Physics (HEP)
DOE Contract Number:
AC02-07CH11359
OSTI ID:
1156433
Report Number(s):
CERN-THESIS-2011-266; FERMILAB-THESIS-2011-47
Country of Publication:
United States
Language:
English