Test of the diphoton + missing transverse energy background model in ATLAS

I present the data and MC comparisons for the selection variables of the two photon + $E_T^{miss}$ final state in ATLAS experiment. The data is taken from the proton-proton collisions of the 7 TeV center of mass energy at the Large Hadron Collider. The data sample studied was the initial 3.1 pb$^{-1}$ taken in the 2010 run. This analysis excluded the gravity mediated One Universal Extra Dimension model with $\Lambda$R=20, N=6 and $\mathrm{M_D}=5$ TeV for a curvature 1/R$\le$ 725 GeV at 95\% C.L., where $\Lambda$ is the cutoff scale, N is the number of large extra dimensions and $\mathrm{M_D}$ is the (4+N)-dimensional Planck scale.