arXiv subjects

Levente Fekésházy

Publications and source records attributed to Levente Fekésházy.

5 recordsLinked to original sources

arXiv2026

NNLOCAL: Fully Local Subtractions for Precision Predictions in Hadron Collisions

This work extends the CoLoRFulNNLO subtraction method to address soft and collinear divergences in the computation of higher-order corrections for hadronic collisions. By utilizing universal local counterterms which can be integrated analytically over the unresolved phase space, we achieve numerically stable, fully-differential predictions. Our publicly available NNLOCAL code serves as a proof-of-concept implementation, validated by calculating the NNLO cross-section for Higgs boson production in gluon-gluon fusion with no light quarks.

hep-ph↗

arXiv2026

NNLOCAL: Completely Local Subtractions

The computation of higher-order corrections to cross sections relevant at LHC involves the evaluation of phase-space integrals that exhibit soft and collinear divergences. The subtraction of these divergences is a key ingredient to obtain fully-differential predictions for physical observables. We discuss a subtraction method to handle these divergences based on the construction of universal local counterterms. The integration of the counterterms is carried out analytically, giving a strong control on the numerical stability of our predictions. We implement our method in a numerical program, that we dub NNLOCAL, and validate it by computing the fully-differential NNLO cross-section for Higgs boson production in gluon-gluon fusion.

hep-ph↗

arXiv2025

LinApart2: efficient parallel partial fraction decomposition algorithm for denominators with polynomials of general degree

We present LinApart2, a major update to the LinApart algorithm for univariate partial fraction decomposition. Unlike its predecessor, LinApart2 can handle denominators of arbitrary polynomial degree without explicit factorization, while retaining the efficiency and parallelizability of the Laurent series method. Benchmarks show substantial speedups in both runtime and memory usage compared to Mathematica's built-in routine Apart and to the Euclidean algorithm, enabling computations that were previously intractable.

cs.SC↗

arXiv2025

Master integrals for semi-inclusive cuts of massless four-loop propagators

We present the analytic calculation of all master integrals for 3-, 4-, and 5-particle semi-inclusive cuts of four-loop massless propagators by means of differential equations. We fix the integration constants by reducing the semi-inclusive integrals to their fully inclusive counterparts with the Integration-By-Parts (IBP) method. We validate our results by calculating the next-to-next-to-next-to-leading order (N3LO) semi-inclusive $e^+e^- \to X$ cross-section and integrating directly over the differential variable. We provide the results in a machine-readable form. The presented integrals are essential for the direct calculation of NNLO time-like splitting functions and N3LO coefficient functions, which play a crucial role in precision QCD calculations.

hep-ph↗

arXiv2024

LinApart: optimizing the univariate partial fraction decomposition

We present LinApart, a routine designed for efficiently performing the univariate partial fraction decomposition of large symbolic expressions. Our method is based on an explicit closed formula for the decomposition of rational functions with fully factorized denominators. We provide implementations in both the Wolfram Mathematica and C languages, made available at https://github.com/fekeshazy/LinApart . The routine can provide very significant performance gains over available tools such as the Apart command in Mathematica.

cs.SC↗