Impact of LHC Heavy-Flavour Data on Nuclear Gluon PDF
Résumé
We use for the first time experimental data for the inclusive heavyquark production in proton–lead collisions at the LHC in order to improve our knowledge of the gluon distribution in nuclei. We first check that the two most recent global nuclear parton distribution analyses (nCTEQ15 and EPPS16) provide a good overall description of the data, and then use these data in a PDF reweighing analysis. We find a first clear confirmation of gluon shadowing at small x. Additionally, it demonstrates that the inclusion of such heavy-flavour data in a global fit would significantly reduce the uncertainty on the gluon density down to x ' 7 × 10−6 while keeping an agreement with the other data of the global fits. Our study accounts for the factorisation scale uncertainties which become the largest for the charm(onium) sector.