Studying the undelaying event in collisions with rare processes is one of very interesting and largely unexplored niches of the LHC physics program. It has multiple implications and helps to understand collectivity phenomena recently observed in small systems, the multi-parton interactions and more. These measurements, however are impeded by the presence of the pileup that significantly limits the accuracy of such studies.

This talk presents the first measurement of two-particle correlations in pp collisions with a Z boson identified via its dimuon decay channel. The analysis uses ATLAS data recorded under nominal pp luminosities, and a procedure to correct for contribution of the tracks coming from pileup vertices is used. Applicability of the method to a broad variety of measurements is shown and discussed.