Search for dilepton resonances in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

TL;DR

This paper reports a search for high-mass dilepton resonances in proton-proton collisions at 7 TeV using the ATLAS detector, setting limits on new particles like Z' bosons and gravitons.

Contribution

First search at 7 TeV for dilepton resonances with ATLAS, establishing new mass exclusion limits for Z' and Randall-Sundrum gravitons.

Findings

No significant excess observed above Standard Model expectations.

Excluded Z' bosons below 1.83 TeV.

Excluded Randall-Sundrum gravitons below 1.63 TeV.

Abstract

This Letter reports on a search for narrow high-mass resonances decaying into dilepton final states. The data were recorded by the ATLAS experiment in pp collisions at sqrt(s) = 7 TeV at the LHC and correspond to a total integrated luminosity of 1.08/fb (1.21/fb) in the ee (mumu) channel. No statistically significant excess above the Standard Model expectation is observed and upper limits are set at the 95% C.L. on the cross section times branching ratio of Z' resonances and Randall-Sundrum gravitons decaying into dileptons as a function of the resonance mass. A lower mass limit of 1.83 TeV on the Sequential Standard Model Z' boson is set. A Randall-Sundrum graviton with coupling k/M_Pl=0.1 is excluded at 95% C.L. for masses below 1.63 TeV.