Multiplicative matching of neutral current deep-inelastic scattering processes at next-to-leading order in PYTHIA 8

TL;DR

This paper presents a new multiplicative matching method for neutral-current deep inelastic scattering in Pythia 8, improving agreement with experimental data and reducing uncertainties.

Contribution

A novel multiplicative matching approach for deep inelastic scattering in Pythia 8 that incorporates first-order corrections and enhances simulation accuracy.

Findings

Better overall agreement with HERA data.

Reduced uncertainties in the simulation results.

Validates higher-order correction implementation.

Abstract

We introduce a method for matching the neutral-current deep inelastic scattering process with parton showers at first order in the strong coupling. This multiplicative matching is achieved by reweighting leading-order Born-level events and requires that the first parton-shower emission is distributed according to the real matrix-element. The method is implemented as an internal matching strategy in the Pythia 8 event generator applicable with both currently available parton shower algorithms, the default one and Vincia. The validity of higher-order corrections is verified with comparisons against existing next-to-leading order simulations. The strategy is used to describe reduced cross-sections measured at the HERA collider, and we find better overall agreement and reduced uncertainties with the matching.