Calculate the Z Mass

Students use momentum conservation, energy conservation and two-dimensional vector addition to calculate the mass of the Z boson.They gather data from event displays of candidate Z decays from the ATLAS and CMS experiments at CERN’s Large Hadron Collider (LHC). The eight events from 2010 were chosen carefully; the momenta of the muons from the Z decay were relatively small in the direction along the beam line. Thus these events were nearly two-dimensional in the plane transverse to the beam line. Treating them as two-dimensional gives reasonable results for the mass of the Z. Image Credit: CERN,CMS