Search for High-Mass e+e- Resonances in pp̅ Collisions at √s=1.96 TeV

A search for high-mass resonances in the e + e - final state is presented based on 2.5 fb -1 of √s = 1.96 TeV pp collision data from the CDF II detector at the Fermilab Tevatron. The largest excess over the standard model prediction is at an e + e - invariant mass of 240 GeV/c 2 . The probability of observing such an excess arising from fluctuations in the standard model anywhere in the mass range of 150-1000 GeV/c 2 is 0.6% (equivalent to 2.5σ). We exclude the standard model coupling Z' and the Randall-Sundrum graviton for k/M Pl = 0.1 with masses below 963 and 848 GeV/c 2 at the 95% credibility level, respectively.