Z Boson Jet Momentum Imbalance in pp Collisions at STAR

Proton-proton collisions at RHIC with center of mass energy 500 GeV produce Z bosons that recoil off jets. In this analysis, Z boson transverse momentum (pT) is compared to away-side jet pT, and the ratio, xjet,Z = pT,jet/pT,Z is measured. Utilizing data from the STAR experiment, the invariant mass method is used to identify Z bosons from their lepton pair decays. Candidate Z bosons are selected with a narrow window around the mass peak near 90 GeV where the back- ground contribution is significantly suppressed. Jets can be identified using the anti-kT algorithm from the Fastjet package. We find that results using STAR 2017 data can be compared with those simulated using the Pythia 8 event generator.