2009: Supersymmetry–if the appropriate energy scale is 1TeV
2009/2010: Higgs particle–if it is around 200 GeV in mass.
2010/2011: Higgs particle–if it is around 120 GeV in mass. (The lower energy is harder to see because at that energy, it would decay with the key signature involving photons. However, other decays also have similar photons so you need better statistics to tell the difference. A Higgs at higher energy would probably decay primarily into W bosons, with very obvious characteristic jets of particles coming out of the collision.)
2012: Extra dimensions of space–if the energy scale is 9 TeV
2012: Compositeness–if quarks are actually composite particles instead of being fundamental and that composite nature reveals itself on an energy scale of 40 TeV.
2017: Supersymmetry–if the appropriate energy scale is 3 TeV.
2019: Z‘–if there is a new type of force that comes into play around the 6 TeV energy scale. If it does, the particle that communicates the force is represented by the temporary name Z‘ in analogy with the Z that transmits the weak force.