Article: Performance of algorithms that reconstruct missing transverse momentum in √s = 8 TeV proton-proton collisions in the ATLAS detector
Authors: The ATLAS Collaboration
Reference: arXiv:1609.09324

The ATLAS experiment recently released a note detailing the nature and performance of algorithms designed to calculate what is perhaps the most difficult quantity in any LHC event: missing transverse energy. Missing transverse energy (MET) is so difficult because by its very nature, it is missing, thus making it unobservable in the detector. So where does this missing energy come from, and why do we even need to reconstruct it?

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