FEWZ 2.0: A code for hadronic Z production at next-to-next-to-leading order

TL;DR

FEWZ 2.0 is an enhanced simulation tool for precise modeling of Z boson production at hadron colliders, offering improved customization, efficiency, and accuracy for LHC physics analyses.

Contribution

The paper presents FEWZ 2.0, a significantly upgraded version of the NNLO Z production simulation code with new features and improved performance.

Findings

Comparison with ATLAS and CMS data shows good agreement.

Enhanced phase-space handling improves measurement accuracy.

Automatic PDF error estimation aids in uncertainty analysis.

Abstract

We introduce an improved version of the simulation code FEWZ (Fully Exclusive W and Z Production) for hadron collider production of lepton pairs through the Drell-Yan process at next-to-next-to-leading-order (NNLO) in the strong coupling constant. The program is fully differential in the phase space of leptons and additional hadronic radiation. The new version offers users significantly more options for customization. FEWZ now bins multiple, user-selectable histograms during a single run, and produces parton distribution function (PDF) errors automatically. It also features a signifcantly improved integration routine, and can take advantage of multiple processor cores locally or on the Condor distributed computing system. We illustrate the new features of FEWZ by presenting numerous phenomenological results for LHC physics. We compare NNLO QCD with initial ATLAS and CMS results, and discuss in detail the effects of detector acceptance on the measurement of angular quantities associated with Z-boson production. We address the issue of technical precision in the presence of severe phase-space cuts.