Search for Randall-Sundrum gravitons in the diphoton channel at CDF

We report on a search for new particles in the diphoton channel using a data sample of p (p) over bar collisions at root s = 1.96 TeV collected by the CDF II detector at the Fermilab Tevatron, with an integrated luminosity of 5.4 fb(-1). The diphoton invariant mass spectrum of the data agrees well with the standard model expectation. We set upper limits on the production cross section times branching ratio for the Randall-Sundrum graviton, as a function of diphoton mass. We subsequently derive lower limits on the graviton mass of 459 GeV = c(2) and 963 GeV = c(2), at the 95% confidence level, for coupling parameters ( k/(M) over bar (Pl)) of 0.01 and 0.1, respectively.