Jet probes of the nuclear and proton wavefunctions in proton--lead collisions with the ATLAS detector

Measurements of high pT processes in ultrarelativistic proton-nucleus collisions are sensitive to changes in the partonic densities arising from the presence of the high-density nuclear environment. Such measurements are thought to serve as a benchmark of the so called "cold nuclear matter" effects, providing the context within which to understand the strong suppression of high pT processes observed in nucleus-nucleus collisions. However, measurements of the centrality dependence of jet production at forward (proton-going) rapidities may additionally shed light on the behavior of the proton wavefunction at large Bjorken-x. The latest ATLAS results for inclusive jets and charged particles in 31/nb of 5.02 TeV proton-lead collisions at the LHC are presented. The centrality in these collisions is characterized through the sum of the transverse energy in the lead-going forward calorimeter. The nuclear modification factors RpPb and RCP are presented for jets and high-pT charged particles as a function of transverse momentum, rapidity and centrality.