Z Boson Asymmetry Measurements at the Tevatron

TL;DR

This paper reports precise measurements of the Z boson forward-backward asymmetry at the Tevatron, leading to the most accurate determination of the effective weak mixing angle from hadron collider data.

Contribution

It provides the most precise measurement of sin^{2}θ^{l}_{eff} from hadron colliders, using full Tevatron datasets and asymmetry analysis.

Findings

Effective weak mixing angle measured as 0.2315 +/- 0.0010 (CDF)

Effective weak mixing angle measured as 0.23106 +/- 0.00053 (D0)

Most precise hadron collider measurement of sin^{2}θ^{l}_{eff}

Abstract

We present measurements of the forward-backward asymmetry (A_fb) in dilepton pair decays of Z bosons produced in ppbar collisions using the full Tevatron dataset. The CDF experiment extracts a value for the effective weak mixing angle parameter sin^{2}\theta^{l}_{eff} of 0.2315 +/- 0.0010 from the A_fb distribution of dimuon events in 9.2 fb^{-1} of integrated luminosity. From dielectron events in 9.7 fb^{-1} of data, the D0 experiment finds sin^{2}\theta^{l}_{eff} = 0.23106 +/- 0.00053, the world's most precise measurement of sin^{2}\theta^{l}_{eff} from hadron colliders and with light quark couplings.