Search for new phenomena in the dilepton final state using proton-proton collisions at √ s = 13 TeV with the ATLAS detector

A search is conducted for both resonant and non-resonant new phenomena in dielectron and dimuon final states. The LHC 2015 proton–proton collision dataset recorded by the ATLAS detector is used, corresponding to 3.2 fb$^{−1}$ at $\sqrt{s}$ = 13 TeV. The dilepton invariant mass spectrum is the discriminating variable in both searches. No significant deviations from the Standard Model expectation are observed. Lower limits are set on the signal parameters of interest at 95% credibility level, using a Bayesian interpretation. Limits on the Z'$_{SSM}$ are set in the combined dilepton channel for masses lower than 3.40 TeV, as well as for the Z' E$_{6}$ models, such as Z'$_{\chi}$ and Z'$_{\psi}$ below 3.08 TeV and 2.79 TeV, respectively. Limits on the llqq contact interaction scale $\Lambda$ are set between 16.4 TeV and 23.1 TeV.