Progress in the NNPDF global analysis and the impact of the legacy HERA combination

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The H1 and ZEUS collaborations have recently presented their final results for the combination of inclusive cross-section measurements taken during Run I and Run II at the HERA collider.

• In this contribution, following an overview of recent progress in the NNPDF framework, we quantify the impact of the legacy HERA dataset on the NNPDF3.0 analysis, finding that it has a very moderate effect in the global fit.
• On the other hand, we also find that a HERA-only fit using the legacy dataset leads to a rather more accurate determination of PDFs as compared to a fit including only the HERA-I data.
• We also explore the sensitivity of the fit with respect to kinematical cuts in the small-x and small-Q region, finding hints of a possible tension between data and theory.