MET performance in 8 TeV data

The performance of missing transverse momentum reconstruction algorithms is presented using 8 TeV pp collision data collected with the CMS detector, corresponding to an integrated luminosity up to $12.2\pm0.5$ fb$^{-1}$. Events with anomalous missing transverse momentum are studied, and the performance of algorithms used to identify and remove those events is presented. The scale and resolution for missing transverse momentum, including the effects of multiple pp interactions in the same, earlier, and later bunch crossings (pileup interactions), are measured using events with an identified Z boson or isolated photon. They are in general well described by the simulation. Advanced missing transverse momentum reconstruction algorithms are also developed specifically to mitigate the effects of large numbers of pileup interactions on missing transverse momentum resolution. Using these advanced algorithms, the dependence of the missing transverse momentum resolution on pileup interactions is reduced significantly.