NNLO QCD corrections to $\gamma \gamma \to Q\bar{Q}$ from Local Unitarity combined with Coulomb resummation and NLO EW effects

Abstract

The Local Unitarity (LU) formalism provides a constructive, integrand-level realisation of the Kinoshita-Lee-Nauenberg (KLN) theorem, by combining loop and phase-space integrals appearing in scattering cross-sections in such a way that their final-state infrared singularities cancel before integration. Supplemented with localised ultraviolet renormalisation, it enables the direct Monte Carlo integration of cross sections at arbitrary perturbative order in four-dimensional spacetime. In this paper, we present its application to the next-to-next-to-leading order (NNLO) QCD total cross sections for heavy-quark pair production in direct photon fusion, involving the contribution from 138 distinct forward-scattering diagrams where external photons couple only to heavy quarks. By combining NNLO QCD with next-to-leading order (NLO) electroweak (EW) corrections and next-to-leading power (NLP) Coulomb resummation, we obtain state-of-the-art predictions for top-, bottom-, and charm-quark production in ultraperipheral hadron collisions and at $e^{+}{e}^{-}$ colliders.

Supplementary material available from publication source, providing access to the raw data presented and including resources for the independent reproduction of our results. The code is available at https://github.com/alphal00p/phique. v2: 75 pages, 19 figures (journal version)

References in corpus (39)

• The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations
• The five-loop beta function of Yang-Mills theory with fermions
• Adaptive Multidimensional Integration: VEGAS Enhanced
• CEPC Technical Design Report -- Accelerator (v2)
• Top-quark pair hadroproduction at next-to-next-to-leading order in QCD
• Threshold resummation for pair production of coloured heavy (s)particles at hadron colliders
• From loops to trees by-passing Feynman's theorem
• Top-quark pair production near threshold at LHC
• Bound-state Effects on Top Quark Production at Hadron Colliders
• Heavy Quark Pair Production near Threshold with Potential Non-Relativistic QCD
• Observation of quantum entanglement in top quark pair production in proton-proton collisions at $\sqrt{s}$ = 13 TeV
• A Tree-Loop Duality Relation at Two Loops and Beyond
• Bottom-quark production at hadron colliders: fully differential predictions in NNLO QCD
• gamma-UPC: Automated generation of exclusive photon-photon processes in ultraperipheral proton and nuclear collisions with varying form factors
• MadNIS -- Neural Multi-Channel Importance Sampling
• Numerical Scattering Amplitudes with pySecDec
• Top-quark pair hadroproduction at NNLO: differential predictions with the MSbar mass
• Mathematical properties of nested residues and their application to multi-loop scattering amplitudes
• Local Unitarity: a representation of differential cross-sections that is locally free of infrared singularities at any order
• Top quark pair production near threshold: single/double distributions and mass determination
• Observation of a pseudoscalar excess at the top quark pair production threshold
• Locally finite two-loop amplitudes for off-shell multi-photon production in electron-positron annihilation
• Automated EW corrections with isolated photons: $t\bar{t}\gamma$, $t\bar{t}\gamma \gamma$ and $t\gamma j$ as case studies
• The MadNIS Reloaded
• Top Quark Anomalous Electromagnetic Couplings in Photon-Photon Scattering at the LHC
• Top quark pair production in the exclusive processes at LHC
• Numerical integration of loop integrals through local cancellation of threshold singularities
• Light-by-Light Scattering at Next-to-Leading Order in QCD and QED
• Exposing the threshold structure of loop integrals
• Differentiable MadNIS-Lite
• Heavy Quark Fragmentation in $e^{+}{e}^{-}$ Collisions to NNLO+NNLL Accuracy in Perturbative QCD
• Graph complexes and Feynman rules
• Search for heavy pseudoscalar and scalar bosons decaying to a top quark pair in proton-proton collisions at $\sqrt{s}$ = 13 TeV
• Dimuon and ditau production in photon-photon collisions at next-to-leading order in QED
• Heavy-quark pair production in polarized photon-photon collisions at next-to-leading order: Fully integrated total cross sections
• Analytic NNLO transverse-momentum-dependent soft function for heavy quark pair hadroproduction at threshold
• NNLO electron structure functions (PDFs) from SCET
• Automated next-to-leading order QCD and electroweak predictions of photon-photon processes in ultraperipheral collisions
• Tropical sampling from Feynman measures