ATLAS Components

It is not just the Electromagnetic Calorimeter that determines if an event is interesting. Other components, such as the Hadronic Calorimeter and the Muon Spectrometer, send different data about the event that also require almost instantaneous analysis. Srini Rajagopalan: "If I was setting up a trigger for the electron, what I would look for is an energy deposition in the electromagnetic calorimeter, and a track in the tracking chamber. If I was looking for a muon, I would look for hits in the muon chamber, and a possible track in the tracking chamber."