- Open Access
DGLAP evolution at with the candia algorithm
Phys. Rev. D 113, 074008 – Published 6 April, 2026
DOI: https://doi.org/10.1103/p6vv-8zph
Abstract
We present a generalization of the -space candia algorithm to next-to-next-to-next-to-leading order () accuracy in quantum chromodynamics (QCD) for solving the Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) evolution equations for unpolarized parton densities in the nucleon. The algorithm is based on logarithmic expansions of the solution and can be extended to all orders in QCD. An expansion equivalent to the exact solution of the DGLAP equation at is presented in the non-singlet sector. Results for approximate parton distribution functions, evolved using the most recent approximations to the DGLAP splitting functions, are provided for benchmarking. The new version of the code, candia-v2, is publicly available [github, candia-v2, (2025).].
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