Oct 4 – 8, 2021
University of Alcalá
Europe/Madrid timezone

The Path to Proton Structure at One-Percent Accuracy

Oct 4, 2021, 10:10 AM
30m
Colegio San Ildefonso (University of Alcalá)

Colegio San Ildefonso

University of Alcalá

Speaker

Juan Rojo (VU Amsterdam)

Description

I review recent progress in the determination of the collinearly-integrated parton distribution functions of the proton. I will focus on the recent NNPDF4.0 determination, a state-of-the-art analysis based on almost independent 100 datasets. NNPDF4.0 is constructed by means of a novel methodology through hyperparameter optimisation, leading to an efficient fitting algorithm built upon stochastic gradient descent. Theoretical improvements in the PDF description include a systematic implementation of positivity constraints and integrability of sum rules. We validate our methodology by means of closure tests and "future tests" (i.e. tests of backward and forward data compatibility), and assess its stability, specifically upon changes of PDF parametrization basis. I will present the implications for NNPDF4.0 for our understanding of nucleon structure, from the proton antimatter asymmetry to the strange and charm quark content. The software framework used to produce NNPDF4.0 is made available as an open-source package together with documentation and examples.

Primary author

Juan Rojo (VU Amsterdam)

Presentation materials