Inclusive open charm photoproduction in ultraperipheral collisions at the LHC with G$\gamma$A-FONLL

TL;DR

This paper introduces the GγA-FONLL framework for predicting inclusive D0 meson production in ultraperipheral Pb-Pb collisions at the LHC, validated against HERA data and compared with CMS results, accounting for nuclear effects.

Contribution

The paper presents a novel GγA-FONLL framework that combines FONLL with photon-flux reweighting to predict heavy-quark production in ultraperipheral heavy-ion collisions.

Findings

Predictions agree with CMS experimental data.

Framework validated against HERA D* photoproduction cross sections.

Results depend on nuclear PDFs, fragmentation, and scale choices.

Abstract

We compute the inclusive $D^{0}$ production cross section in ultraperipheral Pb-Pb collisions at the LHC as a function of the $D^{0}$ transverse momentum and rapidity. These calculations are carried out within the new G$\gamma$A-FONLL (Generalized Photon-Nucleus FONLL) framework, which can predict photonuclear cross sections for charm and beauty hadrons in electron-proton, electron-nucleus, and ultraperipheral heavy-ion collisions. The framework relies on FONLL (Fixed-Order Next-to-Leading Logarithm) to model heavy-quark production in photonuclear collisions and employs a photon-flux reweighting procedure to describe the production cross sections in ultraperipheral heavy-ion collisions. The G$\gamma$A calculations are first validated against the photoproduction cross sections of $D^{*}$ in electron-proton collisions at HERA. The predictions for the $D^{0}$ production cross section in ultraperipheral Pb-Pb collisions at the LHC are then presented and compared to the first experimental results obtained by CMS at $\sqrt{\rm s_{NN}}=5.36$ TeV. The predictions are benchmarked against different choices of nuclear parton distribution functions, fragmentation functions, and renormalization and factorization scales.