LHCb - Probing nucleon structure with fixed-target collisions at LHCb

Thanks to the injection of noble gases in the LHC beam-pipe while proton or ion beams are circulating, the LHCb spectrometer has the unique capability to function as the highest-energy fixed-target experiment ever built. The resulting beam+gas collisions cover an unexplored energy range that is above previous fixed-target experiments, but below the top RHIC energy for AA collisions. In this contribution, we present new results on charm production from $p$He, $p$Ar, $p$Ne, and PbNe fixed-target collisions at LHCb, which provide unique constraints to shed light on the nucleon structure. Comparisons with various theoretical models of particle production and transport through the nucleus will be discussed. Also, prospects with the upgraded fixed-target system will be illustrated.