Eur. Phys. J. C (2016) 76: 614
https://doi.org/10.1140/epjc/s10052-016-4458-1

Regular Article - Theoretical Physics

Underlying-event sensitive observables in Drell–Yan production using GENEVA

¹ CERN Theory Division, 1211, Geneva 23, Switzerland
² Ernest Orlando Lawrence Berkeley National Laboratory, University of California, Berkeley, CA, 94720, USA
³ Theory Group, Deutsches Elektronen-Synchrotron (DESY), 22607, Hamburg, Germany

^* e-mail: simone.alioli@cern.ch

Received: 13 September 2016
Accepted: 24 October 2016
Published online: 9 November 2016

Abstract

We present an extension of the Geneva Monte Carlo framework to include multiple parton interactions (MPI) provided by Pythia8. This allows us to obtain predictions for underlying-event sensitive measurements in Drell–Yan production, in conjunction with Geneva ’s fully differential calculation, resummation for the 0-jet resolution variable (beam thrust), and resummation for the 1-jet resolution variable. We describe the interface with the parton-shower algorithm and MPI model of Pythia8, which preserves both the precision of the partonic N-jet cross sections in Geneva as well as the shower accuracy and good description of soft hadronic physics of Pythia8. We present results for several underlying-event sensitive observables and compare to data from ATLAS and CMS as well as to standalone Pythia8 predictions. This includes a comparison with the recent ATLAS measurement of the beam thrust spectrum, which provides a potential avenue to fully disentangle the physical effects from the primary hard interaction, primary soft radiation, multiple parton interactions, and nonperturbative hadronization.