Search for Diphoton Events with Large Missing Transverse Momentum in 8 TeV pp Collision Data with the ATLAS Detector

A search for diphoton events with large missing transverse momentum has been performed using 20.3 fb$^{-1}$ of proton-proton collision data at a centre-of-mass energy of 8 TeV recorded with the ATLAS detector. No excess of events was observed above the Standard Model prediction and both model-independent and model-dependent 95% confidence level exclusion limits are set. Using a selection optimized to detect evidence for a generalised model of gauge-mediated supersymmetry breaking with a bino-like lightest neutralino $\tilde{\chi}^{0}_{1}$, gluinos below 1280 GeV and degenerate triplets of wino-like charginos and next-to-lightest neutralinos below 570 GeV are excluded for any $\tilde{\chi}^{0}_{1}$ mass above 50 GeV.