Electroweak boson measurements in $p$+Pb and Pb+Pb collisions with ATLAS

Electroweak bosons produced in nucleus-nucleus collisions at LHC energies are excellent probes of the collision geometry and centrality. In proton-nucleus collisions, they provide insight into cold nuclear matter effects such as nuclear modifications of parton distribution functions or initial-state parton energy loss. This report presents the latest ATLAS results on massive electroweak boson production in Pb+Pb and $pp$ collisions at $\sqrt{s_\mathrm{NN}} = 5.02$ TeV using data collected by the ATLAS experiment in 2015, as well as a measurement of prompt photon production in $p$+Pb collisions at $\sqrt{s_\mathrm{NN}} = 8.16$ TeV.