The role of multi-parton interactions in doubly-heavy hadron production

TL;DR

This paper investigates how multi-parton interactions influence the production of doubly-heavy hadrons in proton-proton collisions, highlighting the importance of heavy-quark pair origins and color reconnections, with new simulation methods enabling large-scale studies.

Contribution

It introduces new simulation techniques for heavy-quark events in Pythia and analyzes the impact of multi-parton interactions on doubly-heavy hadron production, emphasizing the role of color reconnections.

Findings

Higher production rates predicted when heavy quarks from different interactions combine.

Simulation speed-ups enable large samples with multiple heavy-quark pairs.

Experimental measurements can differentiate contributions from various multi-parton interaction models.

Abstract

Beauty and charm quarks are ideal probes of pertubative Quantum Chromodymanics in proton-proton collisions, owing to their large masses. In this paper the role of multi-parton interactions in the production of doubly-heavy hadrons is studied using simulation samples generated with Pythia, a Monte Carlo event generator. Comparisons are made to the stand-alone generators BcVegPy and GenXicc. New methods of speeding up Pythia simulations for events containing heavy quarks are described, enabling the production of large samples with multiple heavy-quark pairs. We show that significantly higher production rates of doubly-heavy hadrons are predicted in models that allow heavy quarks originating from different parton-parton interactions (within the same hadron-hadron collision) to combine to form such hadrons. Quantitative predictions are sensitive to the modelling of colour reconnections. We suggest a set of experimental measurements capable of differentiating these additional contributions.