Dipole Showers and Automated NLO Matching in Herwig++

TL;DR

This paper presents the implementation of a coherent dipole shower algorithm with automated NLO matching in Herwig++, improving the accuracy of event simulations and achieving good agreement with experimental data.

Contribution

The paper introduces a new dipole shower algorithm and automated NLO matching modules integrated into Herwig++, enhancing simulation precision.

Findings

Good agreement with LEP, HERA, and Tevatron data

Slight improvement with NLO matching

Enhanced event simulation accuracy

Abstract

We report on the implementation of a coherent dipole shower algorithm along with an automated implementation for dipole subtraction and for performing POWHEG- and MC@NLO-type matching to next-to-leading order (NLO) calculations. Both programs are implemented as add-on modules to the event generator Herwig++. A preliminary tune of parameters to data acquired at LEP, HERA and Drell-Yan pair production at the Tevatron has been performed, and we find an overall very good description which is slightly improved by the NLO matching.