A measurement of the ratio of the production cross sections for W and Z bosons in association with jets with the ATLAS detector

TL;DR

This paper reports a precise measurement of the ratio of W to Z boson production cross sections with jets at 7 TeV, comparing results with theoretical predictions to test the Standard Model.

Contribution

It provides the first comprehensive measurement of W/Z cross-section ratios with jets at 7 TeV, including differential distributions and comparison with advanced QCD calculations.

Findings

Measured cross-section ratios agree with NLO QCD predictions

Differential ratios provide insights into vector boson production dynamics

Results constrain theoretical models and Monte Carlo generators

Abstract

The ratio of the production cross sections for W and Z bosons in association with jets has been measured in proton-proton collisions at $\sqrt{s}$ = 7 TeV with the ATLAS experiment at the Large Hadron Collider. The measurement is based on the entire 2011 dataset, corresponding to an integrated luminosity of 4.6 fb$^{-1}$. Inclusive and differential cross-section ratios for massive vector bosons decaying to electrons and muons are measured in association with jets with transverse momentum $p_T$ > 30 GeV and jet rapidity $|y|$ < 4.4. The measurements are compared to next-to-leading-order perturbative QCD calculations and to predictions from different Monte Carlo generators implementing leading-order matrix elements supplemented by parton showers.