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arXiv · 2401.10319

Determination of the theory uncertainties from missing higher orders on NNLO parton distributions with percent accuracy

The NNPDF Collaboration·Richard D. Ball·Andrea Barontini·Alessandro Candido·Stefano Carrazza·Juan Cruz-Martinez·Luigi Del Debbio·Stefano Forte·Tommaso Giani·Felix Hekhorn·Zahari Kassabov·Niccolò Laurenti·Giacomo Magni·Emanuele R. Nocera·Tanjona R. Rabemananjara·Juan Rojo·Christopher Schwan·Roy Stegeman·Maria Ubiali
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Abstract

We include uncertainties due to missing higher order corrections to QCD computations (MHOU) used in the determination of parton distributions (PDFs) in the recent NNPDF4.0 set of PDFs. We use our previously published methodology, based on the treatment of MHOUs and their full correlations through a theory covariance matrix determined by scale variation, now fully incorporated in the new NNPDF theory pipeline. We assess the impact of the inclusion of MHOUs on the NNPDF4.0 central values and uncertainties, and specifically show that they lead to improved consistency of the PDF determination with an ensuing moderate reduction of PDF uncertainties at NNLO.

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The NNPDF Collaboration, Richard D. Ball, Andrea Barontini, Alessandro Candido, Stefano Carrazza, Juan Cruz-Martinez, Luigi Del Debbio, Stefano Forte, Tommaso Giani, Felix Hekhorn, Zahari Kassabov, Niccolò Laurenti, Giacomo Magni, Emanuele R. Nocera, Tanjona R. Rabemananjara, Juan Rojo, Christopher Schwan, Roy Stegeman, Maria Ubiali. 2024-01-18. Determination of the theory uncertainties from missing higher orders on NNLO parton distributions with percent accuracy. https://arxiv.org/abs/2401.10319

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