Investigation on Part of Work Done by Electroweak Group Ye Li Graduate Student UW – Madison

1. Measurement of Z Forward-backward Asymmetry p p-bar → γ*/Z + X → e+ e- + X Luminosity: 364/pb The method of Matrix Inversion: correct for the distortion in the measurement caused by the detector resolution and photon radiation in the final state. (unfold the detector effect) Chosen for its simplicity and lack of bias

Vertex interaction of Z → l+ l- : - i ( g / cos θw ) γμ (cvl – cAl γ5) in which cvl and cAl are separately vector and axial-vector couplings Discuss in the rest-frame of the lepton pair Define AFB =[ total forward c.s. (cos θ*> 0) – total backward c.s. (cos θ*< 0) ] / total c.s.

Response Matrix: connecting observed values and actual values

The distribution of electron scattering cosθ The distribution of electron scattering cosθ* (below, around and above Z pole)

Unfolded AFB, Agreement with the LO SM calculation is χ2 / ndof = 10

Uncertainty

2. First Measurement of the W Boson Mass with CDF in Run II MW = 80413 ± 48 MeV/c2 (the world's most precise single measurement) Candidates: 63,964 W→e ν 51,128 W→μν Measurement Technique: Extracted from a template fit to the transverse quantity distribution predicted by the MC simulation

Calibration: Uncertainty Momentum Scale Calibration Energy Scale Calibration Recoil Calibration (?) Z recoil tuning Z recoil validation W recoil validation Uncertainty

Momentum scale summary

* Tunning from E/P spectrum Energy scale * Radiative material *

Z recoil tuning (2919 Z→ee and 4960 Z→μμ Events): RMS of η balance vs ZpT RMS of ξ balance vs ZpT

Z recoil validation: Dilepton pT

Transverse Mass Transverse Momentum Transverse Missing Energy

Production and Decay Model: 20 CTEQ6 pairs (?)

Additional W Mass Fits

MW vs M-top Plots