Measurement of the inclusive differential cross section for Z bosons as a function of transverse momentum in pbarp collisions at sqrt{s}=1.8 TeV

TL;DR

This study measures the Z boson transverse-momentum spectrum in proton–antiproton collisions at 1.8 TeV using the DØ detector, focusing on the dielectron decay channel to minimize resolution uncertainties. It combines detailed detector simulation, data-driven background estimation, and Bayesian extraction to obtain a smearing-corrected dσ/dpT, which is then compared to resummed NNLO QCD predictions. The analysis extracts the non-perturbative Sudakov parameter g2 with high precision and confirms good agreement with resummation across the entire pT range, underscoring the reliability of vector-boson production models at high energy. The results have practical implications for precision W mass measurements and Drell-Yan background modeling in collider physics.

Abstract

We present a measurement of the differential cross section as a function of transverse momentum of the Z boson in ppbar collisions at sqrt{s}=1.8 TeV using data collected by the D0 experiment at the Fermilab Tevatron Collider during 1994--1996. We find good agreement between our data and the NNLO resummation prediction and extract values of the non-perturbative parameters for the resummed prediction from a fit to the differential cross section.

Figures (28)

• Figure 1: A cutaway view of the DØ calorimeter and tracking system.
• Figure 2: Electron detection efficiency as a function of electron $E_T$ at the trigger level. The efficiency is essentially flat above our final $E_T$ cutoff of $25$ GeV.
• Figure 3: (a) Mass distribution for all accepted electron pairs, and (b) the $p_T$ distribution for those pairs with $75 < M_{ee}< 105$ GeV.
• Figure 4: Comparison of electron $E_T$, $\eta$, and $\phi$, from $Z$ boson data (crosses) to results of the detector simulation (dashed).
• Figure 5: Illustration of the relationship between the transverse momentum of the electron, the vector $E_T$ of the hadron recoil ($u$) in the calorimeter, and $u_{||}$, the projection of the recoil onto the transverse direction of the electron. In the particular example illustrated here, $u_{||}$ is negative.