Precision Measurements of Electroweak Parameters with Z Bosons at the Tevatron

TL;DR

This paper presents precise measurements of electroweak parameters, including the effective weak mixing angle and an indirect W boson mass, using dilepton asymmetry data from the Tevatron's CDF and D0 experiments.

Contribution

It provides the most accurate electroweak parameter measurements from Tevatron data, improving constraints on the Standard Model.

Findings

Effective electroweak mixing angle: 0.23222 ± 0.00046

Indirect W boson mass: 80.327 ± 0.023 GeV

Consistent results with previous measurements

Abstract

We report on the extraction of $\sin^2\theta^{\rm lept}_{\rm eff}(M_Z)$ and an indirect measurement of the mass of the W boson from the forward-backward asymmetry of dilepton events in the $Z$ boson mass region at the Tevatron. The data samples of $e^+e^-$ and $\mu^+\mu^-$ events collected by the CDF detector correspond to the full 9.4 fb$^{-1}$ run II sample and yield an effective electroweak mixing angle $\sin^2\theta^{\rm lept}_{\rm eff}(M_Z) = 0.23222 \pm 0.00046$. The corresponding result reported by the D0 collaboration with the full 9.4 fb$^{-1}$ $e^+e-$ sample is $\sin^2\theta^{\rm lept}_{\rm eff}(M_Z) = 0.23146 \pm 0.00047$. The CDF collaboration also extracts the on-shell electroweak mixing angle $ \sin^2 \theta_W = 0.22401 \pm 0.00044$ which corresponds to an indirect measurement of the W boson mass $M_W ({\rm indirect}) = 80.327 \pm 0.023 \;{\rm GeV}$. The quoted uncertainties include both statistical and systematic contributions.