Speaker
Description
Electroweak-boson production in hadronic processes is a clean tool for the investigation of the parton distribution functions (PDFs). This is especially true in heavy-ion collisions at the LHC, where the initial state is still poorly constrained by measurements and important for the interpretation of the system evolution. The ALICE experiment can measure W and Z bosons via their leptonic decays in the electron channel at midrapidity ($|\eta_\mathrm{lab}| < 0.8$) and in the muon channel at forward rapidity ($2.5 < \eta_\mathrm{lab} < 4$). The observations at large $\eta_\mathrm{lab}$ are especially important investigating a phase space region that is largely unconstrained by heavy-ion experiments.
This contribution will present the recent ALICE results on electroweak boson measurements in p--Pb collisions at $\sqrt{s_\mathrm{NN}} = 8.16~{\rm TeV}$ and Pb--Pb collisions at $\sqrt{s_\mathrm{NN}} = 5.02~{\rm TeV}$. They include production yields and nuclear modification factors as a function of rapidity and collision centrality. The results are compared to pQCD calculations; those showing a clear evidence of nuclear modification of the PDFs will be highlighted. Finally, the status and progress of the analysis on W boson production in pp collisions at $\sqrt{s} = 13$ TeV will be presented.
